In the twentieth century, there was an epidemic of heart disease that became the number one cause of death in America. In fact, it still is. The research at the time showed an association between the consumption of saturated fats and an increased cholesterol level in the bloodstream. Back then, it was thought that a high cholesterol level was linked to an increased risk of heart disease. Therefore, an assumption was made that saturated fats caused heart attacks.
This became known as the ‘diet–heart hypothesis’ and was adopted as public policy in 1977, despite there not being any conclusive evidence to prove the hypothesis. Despite the mountain of scientific evidence disproving the diet–heart hypothesis, there is still guidance out there to avoid saturated fats in order to reduce the risk of heart disease. In fact, there is an increasing amount of research that shows there is an increased risk of cardiovascular disease by actually lowering your intake of saturated fats! A recent analysis of data from 76 studies, and more than half a million people, found that those who consume more saturated fats have no more risk of heart disease than those who consume less.(1) A recent review published in 2010 pooled together data from 21 unique studies that included almost 350,000 people, approximately 11,000 of whom developed cardiovascular disease (CVD), tracked for an average of 14 years. The review concluded that there is no relationship between the intake of saturated fat and the incidence of heart disease or stroke.(2) Indeed, the body needs saturated fats and cholesterol to function correctly and millions of years of evolution support this. Saturated fats perform the following important functions in the body:
● Provide building blocks for cell membranes and hormones
● Absorb minerals, such as calcium
● Carry fat soluble vitamins, such as vitamins A, D, E and K
● Provide essential fatty acids
The Facts on Cholesterol
There is a lot of talk about ‘good’ and ‘bad’ cholesterol but, essentially, there is just cholesterol. You’ll often here about HDL being the good cholesterol and LDL being the bad cholesterol. However, these are actually both lipoproteins that carry cholesterol around the bloodstream and there is nothing inherently good or bad about them.
We absolutely need cholesterol to carry out essential functions in the body, including the production of cell membranes and hormones (testosterone, progesterone and oestrogen), as well as bile acids that help to digest fat. It is also important in the production of vitamin D, which we know is important for good health. Cholesterol is also important for its role in brain health because it is critical for synapse formation, the connections between neurons and these allow us to think, learn and form new memories. Cholesterol is not water-soluble and as the blood is mainly water, cholesterol needs lipoproteins to carry it around the bloodstream. These lipoproteins also carry other substances, such as triglycerides and phospholipids, but for now we’ll focus on their role with cholesterol.
These protein ‘carriers’ are categorised by their density – low-density LDL or low density lipoprotein, carries cholesterol from the liver to the rest of the body. Cells then attach to these particles and extract fat and cholesterol. Large LDL particles are not harmful but the small, dense LDL particles can potentially be a problem because they can squeeze through the lining of the arteries and, if they oxidise, cause inflammation and damage. Recent research has shown that this inflammation increases the risk of arteriosclerosis.(3) Large LDL particles are not able to penetrate the walls of the arteries and so there is lower risk associated with these.
HDL, or high-density lipoprotein, scavenges cholesterol from the bloodstream, from LDL and from artery walls and carries it back to the liver for recycling. It is easy to see why HDL is seen as ‘good’ because it is taking cholesterol away from the arteries. But why does HDL take cholesterol away from the arteries? It is being taken back to the liver for recycling so that it can be loaded back into other protein carriers and sent out to other cells in the body where it is needed. The body is very efficient with its resources, particularly as cholesterol is so vital to life.
Does the consumption of saturated fats and foods high in cholesterol actually increase the level of cholesterol in the bloodstream? Let’s take eggs as an example because they have come under fire in the past due to their high cholesterol content. One particular study involved people with metabolic syndrome eating three whole eggs daily for twelve weeks, found that plasma triglycerides decreased and HDL cholesterol increased.
Furthermore, there were increases in large HDL and large LDL particles, and there were reductions in total VLDL particles.(4) This study shows that the consumption of eggs changes the profile of cholesterol in the blood favourably, so that we have less of the small, dense particles of LDL and more of the larger particles of both LDL and HDL. As we have seen earlier in this chapter, it is the small, dense particles of LDL that increase the risk of atherosclerosis. The researchers concluded that whole egg consumption, along with a moderately carbohydrate-restricted diet, provides improvements in lipid profiles and insulin resistance in individuals with metabolic syndrome.
The fats that we eat are transported in the bloodstream mainly as triglycerides and this is the vehicle used for transporting fats to cells. This is healthy but, as with all things, when its gets out of balance, then we start to see problems. It is the liver that produces cholesterol, so the amount of dietary cholesterol that one eats has a limited effect on your body’s cholesterol levels.
So why does the liver create more cholesterol? One hypothesis is that this happens as a result of the inflammation in the artery walls caused by the small, dense particles of LDL becoming lodged and oxidised. We know that part of the inflammation process is that new cells and tissue are created, and we also know that cholesterol plays a role in the formation of new cells. If there is chronic inflammation, not only in the arteries but elsewhere in the body, then it makes sense that cholesterol levels would be elevated.
Where do triglycerides fit into the equation? Well, this is how fat is transported through the bloodstream and a person with high triglycerides has a lot of fats travelling through the bloodstream to the cells. This could be as a result of manufacturing too many triglycerides, which essentially means the body is making too much fat, or it could mean that the body is not burning enough fat as energy.
Is high cholesterol actually bad for us? What does the evidence show? There is an increasing body of evidence showing that cholesterol is not the villain it was once considered. It seems that cholesterol has been wrongly accused; however, it isn’t completely off the hook. The evidence does point the finger at the small, dense particles of LDL triggering the inflammatory process in the artery walls.
In addition, it is thought that it is not only the presence of these small, dense LDL particles, but also the quantity of them in the bloodstream that increases the risk factors. Let’s take an analogy to make this a little easier to digest. We’ve talked about cholesterol being carried in the bloodstream by these lipoproteins. Let’s imagine that these lipoproteins are cars. We’ve got large cars for the regular LDL particles and small cars for the small, dense LDL particles. The bloodstream is the highway or motorway. All of the cars on the highway have passengers, which are cholesterol and fats being transported to various parts of the body. In days gone by, scientists thought it was the number of passengers – the amount of cholesterol – that was a risk factor for heart disease. However, the research now shows that it is actually the number of small cars on the road – the small, dense LDL particles – that is more indicative of increased risk of cardiovascular disease. The more small cars we get on the highway, the busier it gets, and the more chance of these cars crashing into the sides – the blood vessel linings. It is when these small, dense particles of LDL get lodged in the blood vessel lining that they can then oxidise and cause inflammation.
Bringing this discussion full circle back to saturated fats, does the consumption of saturated fats increase the number of LDL particles in the blood? The answer is that it has a limited affect on LDL levels in the blood. The research shows that saturated fat, in its limited capacity to affect LDL and cholesterol, actually lowers the number of small, dense LDL particles.(5,6) Research now provides the evidence that the culprit for increased amounts of small, dense LDL particles is, in fact, sugars and refined carbohydrates.(7) In addition, these also lower the amount of HDL and raise the levels of triglycerides. It’s ironic that the dietary guidance of low fat and high carbohydrates – that has been prevalent for decades and still remains to this day – is being proven to actually increase the risk of cardiovascular disease!
In the mainstream, current cholesterol testing determines the total level of LDL, HDL and triglycerides, from which assumptions can be made. However, we are now starting to see the availability of lab tests that can determine the amount of small, dense LDL particles in the blood, using lipoprotein sub-fraction testing, which is helpful in evaluating an individual’s risk of CVD.
1. Chowdhury R, Warnakula S, Kunutsor S, al et. Association of dietary, circulating, and supplement fatty acids with coronary risk: A systematic review and meta-analysis. Ann Intern Med. 2014;160(6):398-406.
2. Siri-Tarino PW, Sun Q, Hu FB, Krauss RM. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Am J Clin Nutr. 2010;91(3):535-546.
3. Coresh J, Kwiterovich PO. Small, Dense Low-Density Lipoprotein Particles and Coronary Heart Disease Risk. JAMA. 1996;276(11):914.
4. Blesso CN, Andersen CJ, Barona J, Volek JS, Fernandez ML. Whole egg consumption improves lipoprotein profiles and insulin sensitivity to a greater extent than yolk-free egg substitute in individuals with metabolic syndrome. Metabolism. 2013;62(3):400-410.
5. Dreon DM, Fernstrom HA, Campos H, Blanche P, Williams PT, Krauss RM. Change in dietary saturated fat intake is correlated with change in mass of large low-density-lipoprotein particles in men. Am J Clin Nutr. 1998;67(5):828-836.
6. Dreon DM, Fernstrom HA, Miller B, Krauss RM. Low-density lipoprotein subclass patterns and lipoprotein response to a reduced-fat diet in men. FASEB J. 1994;8(1):121-126.
7. Siri-tarino PW, Sun Q, Hu FB, Krauss RM. Saturated fat , carbohydrate , and cardiovascular disease. Am J Clinincal Nutr. 2010;(5):502-509.
Are detox diets a myth? Do they really help our bodies to detoxify? The human body is constantly in a state of detoxification each and every day. If it were not detoxing continuously, we would die. It is that simple. So do we need additional detox protocols to provide a helping hand to our detox systems? Lets take a look at how the liver plays a critical role in the detox process. The liver is critically important to our health playing a major role in metabolism, regulating glycogen storage, hormone production, plasma protein synthesis, immunity and detoxification.
If the liver is not working optimally, then these functions will be compromised resulting in poor health outcomes. When the liver becomes overburdened with processing toxins, you’ll feel sluggish and tired as it is having to work harder to eliminate these toxins. At the same time, it has less capacity for it’s other important tasks of producing nutrients the body needs. Common sense tells us to minimise the toxins we put into the body so that the liver doesn’t have to work so hard on detoxification so that it can function optimally on producing the nutrients we need. An example of this is excessive consumption of alcohol as the liver has to work hard to clear this from the system.
An example of this is excessive consumption of alcohol. Even though research shows that there are some health benefits to moderate alcohol consumption, your liver doesn’t buy into this and considers all alcohol as a toxin. The liver will use a large amount of metabolic energy processing the alcohol to eliminate the toxin and purify the blood. Have you noticed how you can feel tired and sluggish the next day even after moderate amounts of alcohol? There is a process going on in the liver that contributes to this and it is directly related to how much one drinks.
Its not just alcohol though that needs to be detoxified by the liver. In fact, the past 50 years have seen tens of thousands of new synthetic compounds introduced into the environment. Artificial substances, drugs, pesticides or heavy metals ingested through food, air pollutants such particulate matter from diesel engines or industrial manufacturing plants, as well as indoor pollution from a myriad of cleaning chemicals and personal care products. Many of these come under the umbrella of xenobiotics.
These are chemical substances found within an organism that are not naturally produced by or expected to be present within. It can also cover substances that are present in much higher concentrations than are usual. All of these contribute to the toxic load the liver has to deal with on a daily basis. Indeed, there is compelling evidence that all of the various chemical agents we are potentially exposed to are a clear risk to our health. With this in mind, it is easy to see why the body may need some assistance with the detox process. We are living in an age of toxic overload and this can take its toll on our inbuilt detox systems. The liver takes on a large part of this burden but can only do so much before it start to get a backlog!
How Does the Liver Detoxify?
In general terms, the detoxification process involves two phases.
Phase 1 Detox
Many of the toxins that enter the body are fat-soluble, which means they dissolve only in fatty or oily solutions and not in water. This makes them difficult for the body to excrete. Fat soluble toxins have a strong attraction to fat tissues and cell membranes, which are made of fatty substances. In these fatty parts of the body, toxins may be stored for years, being released during times of exercise, stress or fasting. The first phase of the detox process involves enzyme activities that include oxidation, reduction, and hydrolysis reactions during which the toxin is ‘activated’ to a more reactive form. The cytochrome P450 is the family of enzymes responsible for phase 1. Essentially, the phase 1 pathway converts a toxic chemical into a less harmful chemical, however, this process generates free radicals. These free radicals are further metabolized in phase 2, becoming water-soluble molecules that can then can be excreted through urine or bile.
Excessive amounts of toxic chemicals can disrupt the P-450 enzyme system by causing over activity or what is called 'induction' of this pathway. This results in high levels of damaging free radicals being produced. If these free radicals are not fully metabolised in phase 2, they can cause damage to liver cells and to DNA within the cells.
Antioxidants such as vitamin C, vitamin E and natural carotenoids can help to reduce the damage caused by these free radicals. We covered the antioxidant system in a previous article on free radicals.
Phase 2 Detox
This is called the conjugation pathway, whereby the liver cells add another substance such as cysteine, glycine or a sulphur molecule to a toxic chemical or drug, to render it less harmful. This process converts chemical toxins and drugs to into a water soluble substances that can be excreted from the body. In order for the phase 2 process to work effectively, the liver requires sulphur containing amino acids (proteins) such as taurine and cysteine. Other nutrients such as glutamine, glycine, choline and inositol are also required.
If high toxic loads are detected in the body, or high xenobiotic loads as it is sometimes called, phase 1 and phase 2 enzymes are normally activated so that more enzymes are present and detoxification occurs at an increased rate. However, some toxic compounds like those in cigarette smoke and charbroiled meats (grilled on a rack over charcoal), increase phase 1 but not phase 2 enzymes. This results in high levels of unstable intermediate molecules that can trigger free radical damage. This increase in circulating free radicals may be part of the mechanism linking the cancer-promoting toxins in cigarette smoke to increased cancer risk.
Looking at it another way, if Phase 1 is working at normal or accelerated rates, but Phase 2 is running slow, we end up with a lot of reactive substances building up in the body that have no way of being excreted from the body. Ideally, we need Phase 2 to be working optimally at all times.
Can Diet Help the Liver to Detox?
So how do we help the liver with the detoxification process and keep it in working optimally? There are plenty of so called ‘liver detox’ diets out there that recommend some type of starvation regime. However, I don’t subscribe to these diets as there is no evidence that they work and can, in some cases lead to negative consequences. In my view, it really comes down to eating a balanced, healthy diet and minimising refined, processed, sugary foods.
Eating organic vegetables and fruit packed with polyphenols, flavonoids, carotenoids, vitamins and minerals will help us to maintain optimal liver health. Eating the right fats will also help your liver so avocados, nuts and olive oil are all good sources of healthy fats. These kinds of foods have been found to be associated with the upregulation, or inducing, of the detoxification enzymes that we discussed above. This leads to more enzymes being present and a faster rate of detoxification. Lets take a closer look.
In general, B vitamins including riboflavin and niacin, glutathione (the body’s main detoxifying antioxidant), magnesium and flavonoids have been shown to assist phase 1 detoxification. Foods rich in B vitamins include eggs, wholegrains, brown rice, chicken, fish and vegetables. Fruits and vegetables are rich in flavonoids that have potent antioxidant properties.
In phase 2 we saw how sulphur containing amino acids are required for efficient detox. Eggs and cruciferous vegetables such as broccoli, cabbage, Brussels sprouts, cauliflower, as well as raw garlic, onions, leeks and shallots are all good sources of natural sulphur compounds to enhance phase two detoxification. Indeed, broccoli has long been considered to play a role in a healthy diet. Broccoli contains significant amounts of a phytonutrient called glucoraphanin, which is metabolized to the biologically active sulforaphane. Research indicates that sulforaphane has the ability to increase the capacity of the liver to detoxify harmful, cancer-causing compounds. Specifically, sulforaphane increases the activity of the liver's Phase 2 detoxification enzymes. As we can see, broccoli is a nutritional powerhouse, however, its worth noting that broccoli sprouts can contain up to 50 times the level of some of the antioxidants found in full-grown broccoli. Sprouts are a particularly excellent source of sulforaphane glucosinolate and indole-3-carbinol, known for their protective effects against carcinogens.
Phase 2 also requires micronutrient coenzymes, including glycine, N-acetylcysteine (NAC), glutamine, glycine, B vitamins, choline and inositol. As mentioned above, efficient phase two detoxification also requires sulphur-containing amino acids such as taurine and cysteine. NAC is a supplement that acts as a precursor to glutathione, which is the master antioxidant in the body and chief detoxifier! There are glutathione supplements available but it is thought that these may not survive the digestive process, therefore, taking NAC could be a better strategy to support phase 2 detox.
Antioxidants such as C, E and beta-carotene as well as minerals such as selenium, zinc can help in the alcohol metabolism if you enjoy the odd glass of wine. There is some research into milk thistle and dandelion root that might help protect liver cells when ridding the body of toxins. Lab studies suggest that silymarin, an extract of milk thistle, acts on biochemical pathways to help with detoxification.
Having said this, it is early days and there have been no large scale, clinical trials on milk thistle so the jury is still out on this. However, milk thistle has been shown to support glutathione production.
MSM is another interesting supplement that has many health benefits. MSM is a good source of sulphur and research has shown that MSM supplementation has been shown to protect the liver from oxidative damage and chemically induced toxicity. In healthy men ten days of MSM supplementation at 50mg/kg body weight reduced markers of oxidative damage and enhanced glutathione levels following exhaustive exercise. Its worth noting that ten days of supplementation is optimal before achieving these results. The ability of MSM to mitigate toxin-induced liver damage and support detoxification is due in large part to the sulfur it provides with cysteine availability being the main rate-limiting step in glutathione synthesis.
Fibre intake is important too as it supports regular elimination, which is crucial for excreting toxins. Brown rice fibre may be particularly beneficial in eliminating fat-soluble toxins.
Interestingly, grapefruit juice decreases the rate of elimination of drugs from the blood and has been found to substantially alter their clinical activity and toxicity. Eight ounces of grapefruit juice contains enough of the flavonoid naringenin to decrease cytochrome P450 activity by 30%.
When considering taking any supplements to assist in the detoxification process it is wise to seek medical advice, particularly if you are on any medication. If you have the all clear, it is wise to take it slowly and introduce any supplement into the diet at lower doses at first.
In summary, your liver looks after you by cleaning up the toxins you put into your body and producing nutrients essential to good health. Modern day life doesn’t help in this respect with the amount of low quality, processed food that is consumed, environmental toxins, excessive alcohol and so on. We really need to look after our liver to support these critical functions it diligently carries out behind the scenes.
Modulation of Metabolic Detoxification Pathways Using Foods and Food-Derived Components: A Scientific Review with Clinical Application
J Nutr Metab. 2015; 2015: 760689.
Induction of Phase 2 Antioxidant Enzymes by Broccoli Sulforaphane: Perspectives in Maintaining the Antioxidant Activity of Vitamins A, C, and E
Front Genet. 2012; 3: 7.
Induction of Phase 2 Antioxidant Enzymes by Broccoli Sulforaphane: Perspectives in Maintaining the Antioxidant Activity of Vitamins A, C, and E.
Published online 2012 Jan 24. doi: 10.3389/fgene.2012.00007
Life is a journey and we only get so much time. But if we start out on our journey with no destination, with no map and in poor health, then we won't get very far. If a captain sets sail but has no idea of where he or she wants to go and has no maps or compass, this captain will be at the mercy of the winds and the currents. It is no different for anyone else in any walk of life. We are the captain of our own life and we decide on our destination, but we need to have a plan and the tools to help us on our journey.
It won't be plain sailing all the time so we need to be fit and healthy with a positive mindset. We'll need to weather some stormy waters from time to time and stay focused. If we don't take the helm, then we'll be at the mercy of the currents of life. Lets embark on a journey with a clear vision for our lives, with clarity in our goals and a plan to achieve them followed by consistent action. I would like to introduce you to a system I use for creating a life plan and taking action on that plan to achieve your gals and realise your vision. I call it O.R.C.A.S and this stands for:
I hope you find it useful in orchestrating your life. Let’s take a closer look.
This is about defining our Life Vision and setting our goals. What is it that we want to achieve in our lives. What do we stand for? What are our outcomes? Do we want a life of great health, freedom, love, fulfilment, financial independence? What is it you want to achieve this month, this year, the next 3 years and so on. Often, when a person is asked what they want, they don’t actually know or it is a very vague notion.
Do you have some new goals or outcomes you would like to achieve? OK. Great, let’s start the process.
Before you write the goals you want to achieve, you have to be clear on the type of goals you are setting. In this process we are interested in outcome based goals: For example:
I will weigh 2001bs at 12% body fat by March 31st 2018.
In this example, we have a very specific outcome and we can step into the future state and visualise what we will see, hear and feel.
If we had a goal that states:
I will eat 500 calories less per day for the next 3 months and eat healthy foods.
This is a behaviour based goal in that it is something you need to do. It states the behaviour we need to adopt to reach our outcomes. In this goal setting process, we are focusing on outcome based goals. A specific outcome we want to achieve. OK, so we have our outcome. Now we need look at our reasons for wanting to achieve this goal.
What are our compelling reasons for wanting this? Without a compelling reason for doing something, we probably won’t sustain our motivation and actions long enough to achieve the goal. This is a major reason why people don’t achieve their goals. They just don't want it enough!
They didn't have enough compelling reasons to take action every day and follow through. So we need to know the compelling reasons of our desired outcomes, otherwise, when the going gets tough, as it surely will from time to time, we won’t have enough motivation to keep on, keeping on! Compelling reasons provide us with the energy to follow through. In fact, I think it is more than motivation. I think we need to be inspired by our life plan and goals. Inspiration gives rise to motivation! Be inspired by your vision. Write down all of the compelling reasons you can think of for achieving your stated outcomes or goals.
What are the consequences of not following through? What will happen if you don’t realise your vision in this life? When I’ve asked myself these questions, the answers come back as being; not realizing my full potential, feeling unfulfilled, being unhealthy, worrying about the future and so on. These are all negative consequences and going through this process motivates me to avoid this pain. Together with the compelling reasons which motivate you toward your vision and goals, and consequences which motivate you away from negative outcomes and emotions, we have a very potent recipe for inspiration, motivation, enthusiasm and energy. This will sustain us on the journey to living the life we have designed for ourselves with a sense of purpose, joy and fulfillment. This in itself will contribute to good health.
We have to take action on our plan, otherwise, we are not going to get to our destination. What are the specific steps we need to take to achieve our outcomes? Perhaps we have written down an outcome that we want to achieve in 1 year. The next step is to break that down into something more manageable. What are the stepping stones to achieving this? What can we achieve in 6 months, in 3 months, in 1 month? What can we achieve in the next week to move us closer to our stated intention?
These are all measurable steps that take us a little bit closer to our bigger outcomes or goals. When we reach our smaller milestones, we feel a sense of achievement, satisfaction and pride. We feel like we are making progress and this boosts our confidence, our self-esteem and our happiness. In my life, progress certainly does equal happiness.
We need to schedule our actions so that there is some structure to our journey and we are not overwhelming ourselves with too much which leads to excessive stress. Time management is very important when creating a roadmap for our lives because it is easier to overestimate what we can achieve in a month, or 6 months or a year. Interestingly, while we overestimate what we can achieve in a year, we underestimate what we can achieve in 3 years! This is why it is important to chunk down our outcomes into to manageable, achievable sizes so that we can schedule them into our daily lives. Imagine achieving those small goals every day and every week. After a few months, this adds up into some major progress.
Let’s take an example.
Let’s imagine that we have a goal to lose 14lbs of body fat. This is our outcome and its part of a life vision to be healthier with much more vitality and energy. However, without some compelling reasons, we might falter a few weeks into the program. So what could be our compelling reasons? Here are a few to start with:
This is a good start and just looking at these reasons is very inspiring and will get us motivated. As part of this exercise we really need to visualize each of these. What can you see, hear and feel when you think about yourself in this future you, having lost the weight, looking great and feeling great?
Let’s take a look at the other side of this equation. What are the consequences to not achieving this goal?
Now these are just examples and they may well be different for each of us. Whatever your consequences of not doing something, visualize them so that you are fully motivated to move away from them.
So now we are inspired, we are motivated, and we've stoked the furnace. We've got a fire in our belly and it's time to take action. I believe that we should never leave the scene of a decision without taking some action, no matter how small. It sends a signal to our subconscious that we are committed to this path and we are getting the ball rolling. So when you’ve committed to achieving this goal, write your action plan.
Think about how long it will take to lose 14lbs of body fat. When do you want to lose this weight for? 2 months time? Break this down into what you need to lose weekly. That’s 2lbs a week for 7 weeks. That is a sustainable amount of weight to lose each week so that is what we are aiming for. Now, what do we need to do to achieve this? Clearly, we’ll need to think about our dietary habits and eating less calories than we expend, but also getting maximum nutrition from the foods we choose. One of the actions could be to research a common sense approach to losing body fat. We’ll also want to think about some physical activity to boost the metabolism. We might also need to buy some new training gear or join a gym, or book some swimming sessions. Whatever actions you put on your list, take some action immediately. Pick up the phone and book that cardio session, go for a brisk walk or prepare a nutritious low calorie meal.
So now we know what needs to be done to achieve our goal, let’s put a schedule together. This is our roadmap and every day, we need to be scheduling in some of those actions to move us a bit closer to our intended outcome. We might have to re-organise our lifestyle and diary somewhat to accommodate our new routine but we already have our compelling reasons to make this happen. On a daily basis, we’ll be making much better food choices because we need to reduce calories and get maximum nutrition from the foods that we are eating. We’ll also be making time for some form of physical exercise, whether that is burst cardio, brisk walking, swimming, biking, running and so on. After a few weeks of this, it is possible that motivation starts to fizzle. We see this time and time again with New Year’s resolutions and by the end of January, most resolutions have gone by the wayside. However, focus on your compelling reasons for achieving your goal and also the consequences of not achieving your goal. Keep on visualizing yourself as if you have achieved your goal and do this every day. What is happening here is that we are building new habits that will stay with us for life. Research shows that doing something on a daily basis for a month creates a new habit. Let’s make sure that we are creating positive, empowering and healthy habits.
In the next article on this topic, we’ll look at how we can integrate the SMART methodology into this framework and also look at some of its limitations.
Getting to Know Your Skin
Did you know that the skin is the largest organ in the body and it comprises about 15% of our bodyweight! Indeed, the total skin surface of an adult ranges from 12 to 20 square feet. That’s a lot of skin! The skin is composed of about 70% water, 25% protein and 2% lipids with 3 main layers that include the epidermis, dermis and subcutaneous tissue.
The epidermis is the top most layer of the skin. It has no blood supply, but it is nourished by the blood vessels in the dermis. The thickness of the epidermis is usually 0.5-1mm, but this is dependant upon where about on the body we are looking. For example, we have thicker skin on soles of our feet and palms of hands.
The dermis is the middle layer of the skin and it is the thickest of the skin layers comprising of a tight, sturdy mesh of collagen & elastin fibres. These fibres are important proteins, as collagen is responsible for structural support and elastin for the resilience of the skin. The dermis is the layer responsible for the skin's structural integrity, elasticity and resilience. Wrinkles arise and develop in the dermis.
Subcutaneous tissue is the innermost layer of the skin located under the dermis consisting of connective tissue and fat molecules. Subcutaneous fat acts as a shock absorber and heat insulator protecting underlying tissues from cold and mechanical trauma. The loss of subcutaneous tissue, which is typically associated with ageing, leads to wrinkles and sagging of the skin.
Functions of the Skin
What is Skin Aging?
Skin aging is a complex process that is determined by both internal and external factors which results in a progressive loss of structure and function. The changes that occur in the skin over time are much more related to the interaction of the skin with the environment than to genetic predisposition. Therefore, in humans, it can be said that skin aging is related to personal lifestyle as well as the chronological clock.
Internal or intrinsic skin aging is driven by factors such as genetics and the natural consequence of physiological changes over time as well as oxidative stress. However, there is not much we can about our genetics so we need to focus on the factors that are within our control. Intrinsic aging is clinically characterised by loss of elasticity and fine wrinkles as well as skin atrophy and prominence of vasculature.
External or extrinsic skin aging is driven to a large extent by environmental factors and external stressors such as ultraviolet radiation (UVR), pollution and lifestyle factors which have been shown to stimulate the production of free radicals and generate oxidative stress. Extrinsically aged skin is characterised by deep wrinkles, rough texture, telengiectasia and irregular pigmentation. Telangiectasia is a condition in which tiny blood vessels called venules widen and cause threadlike red lines or patterns on the skin. These patterns, or telangiectases, form gradually and often in clusters. They're sometimes known as “spider veins” because of their fine and web like appearance. The severity of extrinsic aging depends on skin type, with the features being more prominent in type I or II skin and less noticeable in type III or higher skin. The following table shows the different skin types:
Table 1. The Fitzpatrick skin phototypes
Factors That Accelerate Skin Ageing
We know that skin aging is related to personal lifestyle. It is known, for example, that smoking or excessive exposure to solar radiation and low air humidity causes the appearance of wrinkles. In addition, poor diet and excess alcohol intake, as well as some diseases such as Type II Diabetes can significantly accelerate the premature ageing of the skin.
Throughout our lifetime, we accumulate damage generated by sun exposure or UV radiation. UV causes inflammation, immune changes, and DNA damage that promotes cellular ageing in our skin. Research shows that frequent episodes of serious sunburn can increase your risk of developing skin problems in later life, such as aging (wrinkling) and skin cancer.
DNA absorbs UV light, and the absorbed energy can result in damage to DNA – our genetic material. What happens is that excessive ultra violet radiation (UVR) exposure can break bonds in the DNA. Most of the DNA breakages are repaired by proteins present in the cell, but if the amount of damage is too great, the alterations to the DNA may remain as permanent mutations. The unrepaired genetic damage of the DNA can lead to skin cancers. Of course, we know that staying out in the sun too long gives us sunburn. This is an acute inflammatory reaction that follows excessive exposure of the skin to ultraviolet radiation. Inflammation and the resulting accumulation of reactive oxygen species (ROS) play an important role in skin aging.
UVR consists of both UVA and UVB radiation. It is UVB that is primarily responsible for producing sunburn but because the solar energy reaching the earth is primarily UVA, it also contributes to sunburn and other harmful effects of UV radiation. Most of us are exposed to large amounts of UVA throughout our lifetime. UVA rays account for up to 95 percent of the UV radiation reaching the Earth's surface. Although they are less intense than UVB, UVA rays are 30 to 50 times more prevalent. They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.
UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (photoaging), but until recently scientists believed it didn’t cause significant damage in areas of the epidermis (outermost skin layer) where most skin cancers occur. Studies over the past two decades, however, show that UVA does indeed damage skin cells in the basal layer of the epidermis, where most skin cancers occur.
There is extensive evidence indicating that oxidative stress induced by free radicals otherwise known as Reactive Oxygen Species (ROS) play an important role in the process of skin ageing.(1) In fact, the aging process in the skin is driven by ROS to an extent that is not attained in any other organ. Ultraviolet radiation, cigarette smoke exposure, environmental pollutants, and the natural process of ageing contribute to the generation of free radicals and ROS in the skin.
UVR plays a primary role in generating ROS in skin cells which leads to DNA damage as discussed previously.
Advanced Glycation End-Products (AGE’s)
In the recent years, the role of advanced glycation end products (AGEs) has been increasingly discussed in skin aging, and the potential of anti-AGE strategies has received high interest from pharmaceutical companies for the development of novel anti-ageing cosmeceutical compounds.
Advanced glycation end products (AGEs), also known as glycotoxins, are a diverse group of highly oxidant compounds. The formation of AGEs is a part of normal metabolism, but if excessively high levels of AGEs are reached in tissues and the circulation they can become pathogenic which essentially means they cause disease.
When glucose molecules and other sugars such as fructose attach themselves to proteins, it is called glycation. The binding of sugar to protein causes cross linking of proteins. Cross linked proteins cause more damage by reacting with free radicals and other toxins to create Advanced Glycation End products (AGEs). These AGEs bind to cells at special attachment sites called RAGEs (Receptor for AGEs) and this results in the production of several harmful chemicals damaging tissues. Unfortunately the process of glycation is what damages the surface of the skin by weakening collagen.
Collagen glycation impairs its function in various ways. Inter-molecular crosslinks of adjacent collagen fibres change its biomechanical properties leading to stiffness and a decrease in flexibility. Collagen glycation also makes it resistant to degradation which inhibits its removal and replacement by newly synthesized and functional collagen. As a result, tissue permeability and turnover is impaired. These AGE’s also affect elastin and fibronectin which contributes further to what is known as dermal dysfunction.
As we discussed earlier, AGE’s or glycotoxins are produced in the body, however, they also exist in foods. AGEs are naturally present in uncooked animal-derived foods, and cooking results in the formation of new AGEs within these foods. In particular, frying, roasting, grilling, searing and broiling propagate and accelerate new AGE formation.
The fact that the modern diet is a large source of AGEs is now well-documented. Because it had previously been assumed that dietary AGEs (dAGEs) are poorly absorbed, their potential role in human health and disease was largely ignored. However, recent studies clearly show that dietary AGEs are absorbed and contribute significantly to the body’s AGE pool. These dietary AGE’s are known to contribute to increased oxidant stress and inflammation, which, as we know, accelerates skin aging. They are also linked to the recent epidemics of diabetes and cardiovascular disease. Here is a table of foods with the highest level of AGE’s.
Table 2. Foods with High Levels of AGE's
How to Stop Premature Skin Aging
In these modern times, we are constantly bombarded with all manor of fancy potions with the next sparkly new ingredient that promise to keep us young forever. Sometimes this means that we forget about the basics which may seem a little boring, however, they are tried and tested and highly effective. In the next few sections, we'll take a look at some of the basics that we can implement quickly and easily.
Managing Sun Exposure
Even if you live in a very sunny place, we need to balance the health benefits of sun exposure with the risks of skin cancer. Over the years, the confusion about the ideal levels of sunlight has increased, with different advice being issued by various organisations. In 2010, a group of seven British health organisations issued a ‘consensus statement’ to provide some guidance on sun exposure and vitamin D. This brings together the latest evidence on vitamin D and provides some clarity on what has been a controversial issue. The consensus is that short and frequent spells in the summer sun, several times a week, can increase your vitamin D levels and benefit your health. More specifically, going outside in the sun for 10 to 15 minutes, several times a week, is optimum for increasing vitamin D levels and represents a safe balance between adequate vitamin D levels and any risk of skin cancer.
Our skin has several internal defense mechanisms against UVR. These include melanin and antioxidants. Melanin, the pigment deposited by melanocytes, is the first line of defense against DNA damage at the surface of the skin. It’ job is to scatter and absorb UVR but it cannot totally prevent skin damage.
UVR exposure causes DNA oxidation and the generation of Reactive Oxygen Species (ROS) or free radicals. When these free radicals exceed our capacity to combat them, we get oxidative stress. The reduction of oxidative stress can be achieved on two levels: by lowering exposure to UVR and/or by increasing levels of antioxidant defense in order to scavenge these free radicals. Antioxidants combat oxidative stress and attenuate the damaging effects of reactive oxygen species (ROS). They impair and even reverse many of the events that contribute to toxicity or disease in the skin.
However, chronic exposure to UVR can overwhelm the skin’s antioxidant capacity, leading to oxidative damage, premature skin aging and skin cancer. There are numerous antioxidants in the skin as follows:
Dietary antioxidants play a major role in maintaining the homeostasis of the oxidative balance and we get most of our antioxidants through diet, however, UVR exposure affects the skin antioxidants. Vitamin E, GSH, SOD, catalase, and ubiquinol are all depleted in both the dermis and epidermis layers of the skin when exposed to UVR. Research shows that the oxidation caused by UVR exposure can be prevented to a large degree by prior antioxidant treatment. There have been many studies performed with different antioxidants or combinations of antioxidants and phytochemicals that have found evidence that free radical damage can be prevented to a significant degree. Lets take a closer look.
Many studies have shown that it is possible to delay skin aging and to improve skin conditions through diet and certain nutritional supplements. Nutritional antioxidants act through different mechanisms and in different compartments, but are mainly free radical scavengers.
Since oxidation steps are crucially involved in formation of many AGEs, substances with antioxidative or metal chelating properties, may also have anti-glycating activities. As a result, there is a lot of interest directed towards nutrients and supplements or so called “nutriceuticals,” as natural tools against AGEs and skin ageing. Previously, we discussed that some foods are high in AGE’s and that high temperature cooking methods can increase the AGE content in a food. In contrast, Table 3 below shows foods that have significantly less AGE’s.
Table 3. Foods with Lower Levels of AGE's
It is interesting to note that when chicken is steamed or cooked with lemon, how the AGE is content is much lower. We’ll talk more about cooking methods later in this article.
Eating more fruit and vegetables is a good way to reduce AGE consumption. Dietary phytonutrients, which are found in the pigments of various colourful fruits and vegetables are responsible for this. One type of phytonutrient in particular, called iridoids, which are found in deeply coloured blueberries and cranberries, can lower AGEs in the body.
As we’ve seen previously, free radicals cause damage in the skin at a cellular level. Our natural defences for these free radicals are antioxidants, however, when the free radicals outnumber the antioxidants, they take over and start to cause havoc. That is why it is important to keep our antioxidant levels topped up. Lets take a closer look some of the antioxidants that can help to prevent skin aging.
Vitamin C, also named L-ascorbic acid, is water soluble, photosensitive and is not naturally synthesized by the human body. Therefore, adequate dietary intake of vitamin C is required and essential for a healthy human diet. Vitamin C can be used orally and topically for skin benefits as it helps to stablise the structure of collagen.(2,3) It also plays a role in cholesterol synthesis, iron absorption and increases the bioavailability of selenium.
Vitamin C deficiency can result in impaired collagen synthesis and is also known for causing scurvy, a disease with some manifestations such as fragility, skin lesions, gum bleeding, ease of developing bruises or slow wound healing. Fresh fruits and vegetables such as citrus fruits, blackcurrant, rose hip, guava, chili pepper or parsley are rich in vitamin C.
The vitamin E complex is another important group of antioxidants consisting of a group of 8 compounds called tocopherols. These are potent antioxidants that scavenge free radicals and work synergistically with Vitamin C. Higher amounts of tocopherols are found in vegetables, vegetable oils like wheat germ oil, sunflower oil, safflower oil and seeds, corn, soy and some sorts of meat. The intake of natural vitamin E products helps against collagen cross linking and lipid peroxidation, which are both linked to aging of the skin. However, we need to be careful with the consumption of oils that are high in Omega 6 such as sunflower oil as this can tip the balance of the Omega 3/Omega 6 ratio. Too much Omega 6 is inflammatory and we are ideally looking for a ratio of 2:1 Omega 3 to Omega 6. However, in the US, this ratio is the other way round with Omega 6 consumption far greater than Omega 3 at up to 20:1. This is a highly inflammatory level.
Carotenoids are organic pigments that are produced by plants and algae, as well as several bacteria and fungi. These include beta-carotene, astaxanthin, lycopene and retinol, which are all highly effective antioxidants and have been documented to possess photo-protective properties.
Beta-carotene is the most prominent member of the group of carotenoids. Compared with other carotenoids, the primary role of beta-carotene is its provitamin-A activity but it also a potent antioxidant that combats free radicals. Carrots, pumpkin, sweet potatoes, mangos and papaya are rich sources of beta-carotene.
Supplementation with beta-carotene can enrich the skin and help protect against photo-ageing from UVR and numerous studies show that it is effective in helping to prevent sunburn.(4) In these studies, the supplementation lasted for 7 weeks, with doses greater than 12 mg/d. Treatment periods of only 3–4 weeks, studies reported no protective effect.
Asta what? How do you pronounce that I hear you say! Asta-Zan-Thin is a naturally occurring carotenoid or pigment found primarily in marine organisms such as salmon, krill, shrimp as well as micro-algae. This carotenoid is the pigment that gives salmon their pink color.
Astaxanthin is a very potent anti-oxidant and anti-inflammatory. In fact, it is the strongest antioxidant known and has many other health benefits for the eyes, central nervous system, brain, skin, immune system, exercise capacity and recovery ability. Studies have shown that Astaxanthin showed a significant photo-protective effect and counteracted UVA-induced alterations significantly. The uptake of astaxanthin by fibroblasts was higher than that of beta-carotene, which leads to the assumption that the effect of astaxanthin on photo-oxidative changes was stronger than that of the other carotenoids. A study showed that astaxanthin could interfere with UVA-induced matrix-metalloproteinase-1 and skin fibroblast elastase expression. Indeed, there are numerous studies showing that topical or oral administration of Astaxanthin can prevent or at least minimise the effects of UVA radiation, such as skin sagging or wrinkling.(5-9)
This is a polyphenol found in numerous plant species including grapes, peanuts, fruits, red wine, and mulberries. Studies have shown resveratrol to possess the ability to protect the skin from harmful UV-induced effects because of it’s potent antioxidant, anti-inflammatory, and anti-carcinogenic properties.
The biggest challenge that resveratrol researchers are currently facing is its poor bio-availability. Resveratrol is very quickly metabolized, usually within 30–60 minutes after consumption. Researchers are currently looking at ways to address this problem and to potentially use resveratrol as a viable treatment for skin cancers and diseases, It's early days yet but certainly one to watch out for.(10)
Another compound with strong antioxidant properties is coenzyme Q10 or ubiquinone. This compound is found in every living cell of an organism. It plays an important role in the mitochondria, which are the powerhouses of our cells generating energy. One the mechanisms of ageing is the result of mitochondrial damage caused by free radicals. Coenzyme Q10 activates defense mechanisms, protects body cells from oxidation, and stimulates metabolism and regeneration. It accelerates cell renewal and delays the aging process.
In a double-blind, placebo-controlled study, 33 healthy subjects were given 50 and 150 mg of CoQ10 daily for 12 weeks. The results showed that the intake of CoQ10 limited seasonal deterioration of visco-elasticity and reduced some visible signs of aging. The study also determined significantly reduced wrinkles and improved skin smoothness. Supplementation with CoQ10 did not significantly affect skin hydration and dermis thickness.(11)
Recently, there has been a lot of interest in green tea because of reported health benefits. Tea leaves contain varying amounts of polyphenols, particularly flavonoids. There are four main flavonoids as follows:
A review of numerous studies with Green tea has concluded that both oral consumption and topical application of green tea protects against inflammation and chemical or UV-induced carcinogenesis. Research on epigallocatechin-3-gallate has also revealed promising results in reducing AGE-induced pro-inflammatory changes.(12)
The content of AGEs in food is highly dependent on the method of preparation, like cooking time and temperature. Fried food contains far higher amounts of AGEs than boiled or steamed food as can been seen in Table 2 above. Whether on the grill, in a skillet, or in the oven, browning or charring foods is an indication that AGEs are present.
Approximately 10–30% of ingested AGEs are absorbed in the circulation and dietary AGEs directly correlate with serum levels of AGEs and inflammatory markers in healthy human subjects, respectively. The formation of new dietary AGEs during cooking can be significantly reduced by cooking with moist heat, using shorter cooking times, cooking at lower temperatures, and by use of acidic ingredients such as lemon juice or vinegar. Lets take a closer look at some tips we can use for reducing for reducing AGE’s
Marinate meats in acidic compounds such as lemon, vinegar or wine. The acids will inhibit the formation of AGEs. For example, beef marinated for an hour in a mixture of lemon juice and vinegar will produce fewer than half the AGEs when cooked compared to unmarinated meat.
Chicken or beef cooked in a pot at a lower heat will have significantly less AGE’s than if it was roasted or fried. Just don’t brown the meat first. Another benefit of using a slow cooker is that more nutrients are retained compared with many other cooking methods, and recipes tend to include more vegetables. It can also be more convenient.
Keep It Moist
Steam, stew, poach and braise meats instead of roasting, frying, grilling or broiling. Poaching or steaming chicken cuts AGEs by more than 80% compared to roasting or broiling.
More Home Cooking
Preparing a meal at home gives you more control on the ingredients and how it is cooked. Heavily processed foods tend to contain more AGEs than whole and minimally processed foods.
We’ve covered some ground in this article focusing on the prevention of skin aging and how we can combat aging from the inside with nutrition and cooking methods to reduce AGE’s and oxidative stress that cause premature skin aging. In the next article, we’ll take a look at how we can protect our skin from the outside with topical lotions containing natural antioxidants.
As we get older, we often feel as though we have less energy. Is this a natural part of aging or can we change this? Yes, we can absolutely change this with a well balanced, nutritious diet, regular exercise and a positive mindset. However, we can only operate efficiently within our energy budget. Energy is finite and if we overspend, then just as with a bank account, we'll go into overdrawn territory and there is a price to pay for that. Energy can be viewed as the currency of our lifeforce so we need to manage this like we manage our financial budget.
We've all had days where we feel lethargic and tired and days when we are full of energy. What makes the difference between days like this? There are a lot of factors that impact our daily energy levels including poor diet, lack of sleep, lack of physical exercise, too much physical exercise, too much stress, lack of purpose and so on.
Energy Utilization in the Human Body
The human body is an amazing energy conservation machine. The energy in the food we eat is converted into physical activity, bodily functions, thermal energy and stored fat. How this energy is utilised is dependent on how much we eat and how much physical activity we do. If we consume more calories than are required to keep our bodies running, stay warm and to fuel our physical activity, those excess calories will be stored as body fat.
All bodily functions, from thinking to lifting weights, require energy. Digestion of your food requires energy, the beating of your heart requires energy, even sleeping requires energy! The brain uses up to a whopping 20 percent of our total energy. If we assume an average resting metabolic rate of 1,300 calories, then the brain consumes 260 of those calories for synaptic activity and just keeping things going. Glucose is virtually the sole fuel for the human brain, except during prolonged periods of starvation. The brain does not have its own fuel store so it requires a continuous supply of glucose.
Our muscles use glucose and fatty acids for fuel. Muscle differs from the brain in that they can store large amounts of glycogen. In fact, about three quarters of all the glycogen in the body is stored in the muscles. The heart muscle functions almost exclusively aerobically, as evidenced by the density of mitochondria in heart muscle. Moreover, the heart has virtually no glycogen reserves. Fatty acids are the heart's main source of fuel, although ketone bodies as well as lactate can serve as fuel for heart muscle.
The kidneys require large amounts of energy to work optimally. Although constituting only 0.5% of body mass, kidneys consume 10% of the oxygen used in cellular respiration. During starvation, the kidney becomes an important site of gluconeogenesis and may contribute as much as half of the blood glucose. The liver is essential for providing fuel to the brain, muscles, and other peripheral organs. Indeed, the liver, which can be from 2% to 4% of body weight, is the metabolic hub in our bodies. Most compounds absorbed by the intestine first pass through the liver, which then regulates the level of many metabolites in the blood. As we can see from this, the body requires a substantial amount of energy to keep everything running smoothly and to keep us warm. We get this energy from the food we eat which has to be broken down in to the biomolecules that sustain life.
Metabolism is the chemical processes that occur within a living organism in order to maintain life. It is a collection of chemical reactions that takes place in the body's cells to produce energy. There are thousands of metabolic reactions happening at the same time, which are all regulated by our bodies to keep our cells healthy and working.
Metabolism can be divided into two categories:
Anabolism is necessary for growth, maintenance and repair of tissues where as catabolism is necessary for energy production. Catabolism and anabolism occur simultaneously all of the time but they differ in magnitude dependent on your level of activity level, rest and the food you’ve eaten recently. When anabolism exceeds catabolism, we get net growth, but when catabolism exceeds anabolism, we get a net loss and body tissues are broken down. A healthy metabolism needs many nutrients for optimal function and indeed, the antioxidants and phytochemicals discussed in this book can have an anti-catabolic state and increases anabolism which is beneficial for faster recovery from strenuous training and higher levels of performance.
The Metabolic Set Point & BMR
The body seeks to maintain a certain base rate of metabolism which is known as the metabolic set point. It is the average at which your metabolism runs. This results in the basal metabolic rate (BMR) which is the total energy conversion rate of a person at rest. The metabolic set point is controlled by your genetics and environmental factors but it can be changed through diet and training. People with a slow metabolism seem to store fat more easily whereas people with a fast metabolism seem to be able to eat whatever they want and not store fat. Research shows that when a person goes on a low calorie diet, the body’s metabolic set point lowers in order to conserve energy, which makes it more difficult to lose weight. This is the reason that so many dieters hit a plateau and progress halts.
Managing Our Energy
Without managing and optimizing our energy levels, we can feel tired, lethargic and unmotivated. Rather than heading to the gym or out for a walk, its easier to head for the sofa! When we are tired, it is easier to make poorer diet choices as convenience offers an easy way out. Therefore, I think it is important to manage and opimise our energy levels and watch out for those dietary or lifestyle choices that rob us of energy. Lets take a closer look.
Poor Diet & Nutrition
Eating the wrongs foods is clearly not going to provide the high quality energy that we need to get us through the day, let alone doing some physical exercise. In fact, some foods rob us of energy and can make us feel sluggish and lethargic. We could write a whole book on the subject of diet and energy but for now, lets just cover the basics. We’ve already discussed the glycemic index and this is key to getting sustained energy from our foods. Consuming high glycemic foods cause our blood glucose to spike leads to peaks and troughs in our energy levels. Have you ever had a snack or a meal that made you feel more hungry and feeling fatigued a few hours later? This is a phenomenon called ‘rebound hypoglycemia’ which occurs when a high glycemic meal of food is eaten. This causes blood sugar and insulin to spike and subsequently, the blood sugar will then drop below levels before the meal leaving you hungry and fatigued. This opens the door to eating more sugary snacks or drinking caffeine beverages to restore energy levels and the cycle starts again. This is not good for our energy levels and over time, can lead to insulin resistance.
Some foods just don’t digest very well and if this is happening, in addition to the digestive discomfort we feel, we are not converting those foods to energy very efficiently. We are using energy to fight the digestive battle that is going on. I know that there are certain foods that really give me indigestion and make me feel sub par. I generally steer clear of these foods. If you have a lactose intolerance, then you’ll no doubt have experienced the bloating and discomfort that comes with consuming over your quota of milk. This kind of discomfort doesn’t motivate us to go for a run!
Looking After Our Digestive Systems
Eating should not be taken for granted. The proper digestion of food requires developing good eating habits. For some people, there are foods that just do not agree with them and as a result, they get indigestion, heartburn, bloating, stomach pain and cramps. If a particular food is having this effect on you, it is time to say farewell to that food.
There are certain foods that I like, but unfortunately, they don’t like me for some reason. I have a lactose intolerance and can only digest so much milk. If I have over my quota for the day, then I’m in trouble! I like spicy foods too, but if I overdo it with the chilli peppers, then, I know about it. Cucumber is another one that gives me indigestion, which is a shame, because I like cucumber in a fresh, crisp salad. One might think, what could possibly be in cucumber that gives you indigestion? It is a substance known as cucurbitacin that can cause indigestion in some people. So you have to listen to your body and take appropriate action.
To get the most mileage out of your meals the following points should be considered.
Dehydration can affect our energy levels and mental clarity through the day. Mild dehydration is defined as approximately 1.5 percent loss in normal water volume. Dehydration can have a range of effects upon the body including:
There may be other longer term health problems that are caused by dehydration:-
A recent study, published in the British Journal of Urology, stated that increasing water intake can reduce risk of kidney stones. During athletic events, intense aerobic sessions or heavy workouts, particularly in hot weather, it is not uncommon for athletes to lose 6–10% of body weight in sweat loss. Decreases in physical performance in athletes have been observed under much lower levels of dehydration, as little as 2%. Even under relatively mild levels of dehydration, individuals doing rigorous physical activity will experience a decrease in performance related to reduced endurance, increased fatigue, reduced motivation, and increased perceived effort.
Relying on thirst alone, might not help us to avoid dehydration as the process may have already started by the time our bodies get to telling us about it. How much water should we be drinking to avoid dehydration? There are all sorts of claims out there on this topic and this can be a confusing topic. We get a lot of water from the food we consume so it really does depend on the types of food we are consuming as to how much additional water we need on top of this.
Caffeine also acts as a diuretic, which means that it makes your body lose water so drinks with caffeine will negatively impact your water intake. A study published in the European Journal of Epidemiology found that water loss due to caffeine corresponded to 1.17ml per mg of caffeine. This works out at a loss of nearly 164ml of water per mug of filter coffee based on a mug containing 140mg caffeine.
This same same study found that alcohol causes a water loss of 10ml per gram of alcohol. Therefore, for a large (250ml) glass of wine of average strength (13%) The alcohol content of the glass is 32.5ml, which equates to 25.6g of alcohol. This means that the body will lose 256ml of fluid, which is a higher volume than the glass of wine itself!(498)
Your level of exercise will also affect your requirement for water, particularly in the summer months. Therefore, recommended daily water intake is going to very from person to person. There are many different opinions on how much water we should be drinking every day. The health organizations generally recommend eight 8-ounce glasses, which equals about 1.82 liters. This is called the 8×8 rule and while there is no clinical evidence to support this, it is easy to remember.
The European Food Safety Authority (EFSA) recommends an intake of 2.5 litres of water for men and 2.0 litres of water for women per day, via food and drink consumption.(500) Of this, they suggest that 70-80% of the daily water intake should come from drinks, and the remaining 20-30% should come from food.
In the next article on the the topic of energy, we'll take a closer look at how exercise impacts our energy levels and how much sleep we need to ensure we are performing optimally through the day. Thanks for tuning in.
There is a huge amount of conflicting information in the media about consuming fish because of the risk of mercury toxicity versus the health benefits. Mercury is a toxic heavy metal which cycles through the atmosphere, water and soil in various forms. The oceans have the ability to act as a storage warehouse for mercury and recent studies show that an estimated 45,000 to 80,000 metric tons has been released into the oceans and that two thirds of this is estimated to be found in waters shallower than 1000 metres where many of the fish that we consume live.
Mercury contamination in the ocean is a serious issue that cannot be ignored. In this article we take a closer look at where the mercury comes from, how it gets into the food chain, the health benefits of eating fish versus potential mercury toxicity. We'll review the advisories from the government agencies and also take a look at the research and evidence so that we can make an informed decision.
The Source of Mercury in Oceans
Mercury is released in several ways which include both natural and anthropogenic processes which is defined as humans activities in exploiting and modifying the environment. Natural processes are mainly from volcanic activity and land emissions. When volcanoes erupt, they release mercury that is stored in the underground resevoirs. Mercury emissions from the land usually occur in the regions closer to the boundaries of tectonic plates where soils are rich in compounds that contain mercury. Natural weathering of the rocks and geothermal reactions can release this mercury. These natural phenomena account for a percentage of mercury emissions today, but anthropogenic emissions have increased mercury concentration in the environment by threefold. Mercury is spewed into the air from coal-burning power plants, steelworks and factories. That pollution can travel halfway around the world and then settle into lakes, rivers, and oceans. Other sources include cement production, consumer products waste and contaminated sites.
How Mercury Gets into the Food Chain
There are various ways that mercury finds its way into the oceans. The largest source of mercury in the ocean is deposited from the atmosphere. In addition, mercury enters the ocean via rivers, estuaries, sediments, and, hydrothermal vents. These sources also release organic mercury compounds such as methylmercury.
This type of mercury is known to be the most poisonous among the mercury compounds and is created when inorganic mercury circulating in the general environment is dissolved into freshwater and seawater. The mercury is then absorbed or ingested by small organisms and then it starts working its way up the food chain, becoming more concentrated with each step. That’s why larger, longer-living predators such as sharks and swordfish tend to have much higher levels of mercury than smaller fish such as sardines, sole, and trout. When you eat seafood containing methylmercury, more than 95 percent is absorbed, passing into your bloodstream. It can move throughout your body, where it can penetrate cells in any tissue or organ. Under certain conditions, methylmercury can negatively affect the central nervous system, particularly the developing brain of a fetus.
Health Benefits of Fish versus Mercury Risks
Fish has always been recognized as an excellent source of protein. In more recent years, cold-water fish have also been recognized as excellent sources of omega 3 fatty acids, including DHA and EPA. Risk of mercury contamination, however, has thrown some of these nutritional benefits into question, and the benefits-versus-risks of fish have become a matter of widespread debate. Do the nutritional benefits of fish, including their rich omega-3 fatty acid content, outweigh the risk of mercury exposure? Lets take a look at the research.
Based on my research, the nutritional benefits of fish certainly do outweigh the risk of mercury exposure, however, we need to take a few factors into account. The FDA and EPA issued recommendations about seafood in 2004, advising no more than 12 ounces of fish per week because of concerns about exposure to mercury. These guidelines were initially intended for women of childbearing age and pregnant women.
It seems that these recommendations have become an accepted fact among the mainstream media, the medical establishment, and the general public. But do these guidelines stand up to scrutiny? Are we robbing ourselves of a great source of protein and omega 3 fatty acids by restricting our fish intake based on these guidelines? Is it possible that pregnant women might not be getting enough omega 3 by following the FDA/EPA guidelines?
An FDA analysis of fish consumption data found that 50 percent of pregnant women surveyed actually ate fewer than 2 ounces a week, far less than the amount recommended. Because the nutritional benefits of eating fish are important for growth and development during pregnancy and early childhood, the agencies updated their advice by recommending a minimum level of fish consumption for these groups. The advice now recommends 2-3 servings of lower-mercury fish per week, or 8 to 12 ounces.(2)
In the 2017 EPA-FDA advice about eating fish, the agencies have concluded that the following people should eat more fish that is lower in mercury for important developmental and health benefits:
The advice recommends that women and children eat two to three servings (8-12 ounces for adults and children over age 10, smaller amounts for younger children) of a variety of fish and shellfish each week.(1) The question still remains, however, on whether we should we be eating more than 12 ounces per week to get the health benefits? Does this advice on a maximum limit of weekly fish consumption have any evidence to support it? What are the factors we need to take into account? Lets dig a little deeper into this.
Mercury and the Brain
Do you know the phrase ‘mad as a hatter’? One theory as to where this phrase came from is related to mercury poisoning experienced by hat-makers as a result of the long-term use of mercury products in the hat-making trade in 19th century England. Mercurial disease was common among hatters and included such symptoms as tremors, irritability, and mental instability.
Today, many studies show that high exposure to mercury induces changes in the central nervous system, potentially resulting in irritability, fatigue, behavioral changes, tremors, headaches, and cognitive loss. Mercury is harmful to the brain because of the toxic increase in reactive oxygen species (ROS). The brain uses a lot of oxygen, in fact, nearly 25% of the oxygen we breathe is used in the brain, but this process produces oxygen by-products through the process of oxidation that creates these reactive oxygen species (ROS) also known as free radicals. These free radicals damage the fats and proteins that make up the brain and research shows that this oxidative damage plays a role in the development and progression of neuro-degenerative diseases.(3)
The brain is very particular about what it lets in and therefore, we have something called the blood brain barrier to prevent undesirable compounds from getting through. Mercury, however, has found a loophole to get through this barrier and when it does, it can cause serious problems under certain conditions. Methylmercury can sneak across the blood brain barrier by binding to an amino acid called cysteine which can be found in foods such as meat, eggs and dairy. So it gets into the brain disguised as an amino acid. Fortunately, it can also be inhibited by other amino acids which means that a high protein diet can help to prevent the transport of methylmercury into the brain. Should we try to avoid cysteine in our diets? Absolutely not because cysteine plays an important role in the body and is a precursor to the potent antioxidant glutathione which we will discuss later in this article.
Mercury and Cardiovascular Disease (CVD)
For decades, the toxic effects of mercury were associated mainly with the central nervous system, however, methylmercury also produces profound cardio-toxicity. Research shows a correlation between mercury exposure and increased risk of hypertension, the progression of atherosclerosis and cardiovascular disease.(4)
The mechanism by which mercury produces toxic effects on the cardiovascular system is not fully understood, but it is believed to involve an increase in oxidative stress. Exposure to mercury increases the production of free radicals and a reduction in the activity of antioxidant enzymes, such as glutathione peroxidase. Research is also showing that mercury levels are predictors of the levels of oxidized low-density lipoprotein (LDL). Oxidized LDL particles are frequently found in atherosclerotic lesions and are associated with the development of atherosclerotic. Another mechanism by which mercury exerts toxic effects on the cardiovascular system is through the inactivation of the “paraoxonase”, an enzyme that slows the LDL oxidation process and that has an important anti-atherosclerotic action.(5)
The Role of Selenium
Selenium is an essential trace mineral that is important for many bodily processes, including cognitive function, a healthy immune system, and fertility in both men and women. It contributes to thyroid hormone metabolism and DNA synthesis, and as an antioxidant, it helps to protect against oxidative damage.
Dietary sources include brazil nuts, fish, brown rice, and eggs are also good source. The amount of selenium in food often depends on the selenium concentration of the soil and water where farmers grew or raised the food. Selenium is known to play an important role in mercury exposure because it prevents mercury toxicity. Research has shown that selenium consistently counteracts the adverse effects of mercury exposure.(6) Mercury is harmful because it deactivates selenium dependent enzymes called selenoenzymes. These are extremely important in the brain because they help to prevent oxidative damage. Mercury interferes with selenonzyme function by binding to selenium and when the level of mercury is high enough, it inhibits the function of selenonzymes preventing them from scavenging free radicals in the brain. Selenium is absolutely required for activity of these selenoenzymes. In fact, all forms of life that have nervous systems possess selenoenzymes to protect their brains from oxidative damage.
Research is showing that it is the ratio of selenium to mercury that matters, regardless of the absolute levels of mercury. When there is more selenium that mercury, the mercury cannot affect proteins or disrupt cell function. It is the total amount of both mercury and selenium consumed over time that is the important factor rather than the absolute levels of mercury within a given fish. Selenium to mercury ratios in excess of 1:1 are thought to counteract the adverse effects of mercury, protecting against mercury toxicity. Evaluation of the health risk posed by mercury exposure from seafood consumption requires consideration of selenium content as well.(7)
Therefore, as long as you are eating wholesome food rich in selenium or eating fish that contains more selenium than mercury, the amount of selenium in the body will always be in plentiful excess of mercury. That means that these essential selenoenzymes can get on with their job without being compromised by mercury. Fortunately, most fish that we consume has more selenium than mercury. However, there are exceptions. These are pilot whale, shark, tilefish, king mackerel and swordfish. Ocean fish generally contain far more selenium than mercury, and protect against rather than contribute to mercury toxicity. However, consumption of fresh water fish that have high mercury, but poor selenium content may pose far greater risks of toxicity than has previously been expected.
Unfortunately, the well-documented protective effect of selenium is largely ignored in both the medical community and the media when reporting on potential risks of fish consumption.
The Role of Glutathione
Glutathione is a peptide containing three important amino acids that have several important roles in the human body. It is a potent antioxidant that prevents damage to cells caused by reactive oxygen species. Researchers have suggested that cellular glutathione levels are a good predictor of life expectancy.
Glutathione has several roles in protecting the body from mercury toxicity. First, glutathione, specifically binding with methylmercury, forms a complex that prevents mercury from binding to cellular proteins and causing damage to both enzymes and tissue. Glutathione-mercury complexes also reduce intracellular damage by preventing mercury from entering tissue cells and becoming an intracellular toxin.(8)
Second, glutathione-mercury complexes have been found in the liver, kidney, and brain, and appear to be the primary form in which mercury is transported and eliminated from the body. Glutathione increases the antioxidant capacity of the cell, providing a defense against ROS and free radicals produced by mercury. As an antioxidant, glutathione appears to also protect against renal damage resulting from methylmercury toxicity. Glutathione works by facilitating the efflux or out-flow of mercury from the cells so that it can be excreted and also by the protective binding of mercury to prevent cellular damage.
Research published in 2006 showed that the depletion of glutathione increased methylmercury accumulation and increased oxidative stress caused by methylmercury. Conversely, supplementation with a glutathione precursor protects against methylmercury exposure in vitro. In vitro refers to the technique of performing a given procedure in a controlled environment outside of a living organism.(9)
Glutathione is poorly absorbed by the body. It seems the beneficial effect of glutathione can only be realized when the precursors are absorbed and the glutathione is manufactured in each and every cell. One such precursor is N-Acetyl-Cystine.(NAC) This is a modified version of the sulfur-containing amino acid cysteine. It replenishes intracellular levels of glutathione, helping to restore cells’ ability to fight damage from reactive oxygen species.(10) Whey protein also replenishes glutathione by boosting cysteine which helps rebuild glutathione levels.
Recommendations on Fish Consumption
The dietary safety limit for methylmercury set by the Environmental Protection Agency is 0.1 microgram per kilogram of body weight per day. Based on that, a blood level of 5.8 micrograms per litre of blood is what the agency considers a maximum acceptable level. But that guideline was set more than a decade ago. Some scientists and consumer safety advocates believe it should be changed because several studies published since then say adverse effects could occur at lower mercury blood levels.
However, given the latest research into the selenium and mercury ratio, perhaps the advice from the FDA and EPA is flawed. Who do we believe? How much fish can we eat without worrying about mercury toxicity? Based on the information and research available, we can make an informed decision for ourselves that makes sense. Lets take a closer look.
We are looking to eat fish that has more selenium that mercury and we want to avoid fish that is higher in mercury than it is in selenium. Generally speaking, most fish consumed by people have higher levels of selenium than mercury, making them perfectly safe to eat. Fish types with more selenium than mercury include the following but this is not an exhaustive list:
The fish that is considered unsafe due to having a greater amount of mercury than selenium include:
Omega 3 Fatty Acids
Omega 3 fatty acids are essential to good health and deficiencies are linked to chronic disease. These polyunsatured fatty acids (PUFAs) have many benefits including brain health, cardiovascular health, and they also have potent anti-inflammatory properties. Many people today are deficient in Omega 3 fats and consume far too much Omega 6 fats found in vegetable oils and processed foods.
Therefore, there is a severe imbalance between omega 3 and omega 6 which can lead to chronic disease. There are several Omega 3 fatty acids that we need to know about. DHA or Docosahexaenoic Acid is a long chain Omega 3 fatty acid and is important for brain and eye development and function as well as cardiovascular health. DHA is the most abundant omega 3 in the brain making up about 15 to 20 percent of your brain’s cerebral cortex. DHA is also abundant in retina making up 30 to 60 percent of the retina so it is easy to see why this is such an essential fatty acid. Low levels of DHA have been linked to memory loss, Alzheimer’s disease, depression and Bipolar disorder. EPA or Eicosapentaenoic Acid as a long chain Omega 3 fatty acid which is important for overall health. However, EPA is not stored in the body in any significant amount like DHA.
Fish is a fantastic source of omega 3 so it makes sense to include plenty of fish in our diet. The table below lists some of the seafood that are a good source of Omega-3 fatty acids and have more selenium than mercury, ranked by DHA/EPA levels.
Table 1. Good sources of omega 3 with a good selenium to mercury ratio.
What’s the Deal with Canned Tuna
According to a February 2007 Environmental Protection Agency’s (EPA) report, 39% of all mercury exposure from fish in the U.S. comes from tuna. Of this 39%, 18% comes from canned light tuna, 10% from canned albacore or white tuna, and 11% from fresh or frozen tuna.
There are two main kinds of canned tuna:
All canned white tuna is albacore. In the EPA update report, both Pacific and Atlantic albacore tuna (all forms, including canned and fresh) contained about triple the mercury content of both Pacific and Atlantic light tuna (yellowfin). The EPA reports that the mercury levels in albacore tuna are almost three times higher than yellowfish or skipjack. Canned light tuna is made up mostly of skipjack tuna.
From the perspective of absolute mercury levels in canned tuna, it is clear that light tuna (especially Pacific light tuna) — is better than albacore tuna (especially Atlantic albacore tuna) but should we be avoiding canned tuna based on this? If you use the selenium to mercury ratio as a basis to make this decision, then the answer is no. Tuna has a higher selenium to mercury level and is also rich in essential omega 3 fatty acids as can be seen in the Table 1 above. We might want to apply some moderation to canned tuna intake simply because it is taking up space in your diet and it is a canned product, whereas you could be eating fresh fish that also has a good selenium to mercury profile and a high level of omega 3 fatty acids. It is also creating more variety in your diet.
Sustainable Seafood Considerations
Bluefin tuna, have been so overfished that they can't reproduce fast enough to replace what's caught. If you care about sustainability, they should be on your do-not-eat list. How fish are caught also affects their sustainability. Longlining can be especially devastating because it involves one line that can have 3,000 baited hooks and stretch for up to 50 miles. The hooks dangle at a depth between 328 feet and 492 feet where the largest tuna—such as the threatened bluefin—tend to swim.
Many albacore are now caught by longlining too. These hooks also catch more than 80 kinds of non-targeted creatures, including endangered sea turtles so again, this is not an eco-friendly way to fish. A number of yellowfin populations are overfished now, so only pole-caught fish are considered a good choice for sustainability.
Should we be eating more than the 12 ounces per week recommended as a maximum by the FDA? The research suggests that we can indeed eat more than this because the net health benefits of consuming fish far outweigh the risks of mercury toxicity when we consume fish with a higher selenium to mercury ratio. These types of fish contain high levels of omega 3 fatty acids which are essential for good health and are a good source of protein. However, not everyone is a a fan of eating fish so these people my not be getting adequate amounts of Omega 3 fatty acids which are essential for health. If this is the case for you, it is best to take a high quality fish oil supplement that is derived from sustainable sources or include other foods in your diet that are rich in Omega 3.
3. Oxidative Stress in Neurodegenerative Diseases: From Molecular Mechanisms to Clinical Applications. Oxid Med Cell Longev. 2017; 2017: 2525967.
4. Fish, Mercury, Selenium and Cardiovascular Risk: Current Evidence and Unanswered Questions. Int J Environ Res Public Health. 2009 Jun; 6(6): 1894–1916.
5. Toxic Effects of Mercury on the Cardiovascular and Central Nervous Systems. J Biomed Biotechnol. 2012; 2012: 949048.
6. Selenium and Mercury Interactions with Emphasis on Fish Tissue. Environmental Bioindicators 4(4):318-334 · December 2009.
7. Selenium/mercury molar ratios in freshwater, marine, and commercial fish from the USA: variation, risk, and health management. Rev Environ Health. 2013;28(2-3):129-43.
8. Mercury toxicity and antioxidants: Part 1: role of glutathione and alpha-lipoic acid in the treatment of mercury toxicity. Altern Med Rev. 2002 Dec;7(6):456-71.
9. Glutathione modulation influences methyl mercury induced neurotoxicity in primary cell cultures of neurons and astrocytes. Neurotoxicology. 2006 Jul;27(4):492-500.
10. The Antioxidant Role of Glutathione and N-Acetyl-Cysteine Supplements and Exercise-Induced Oxidative Stress. J Int Soc Sports Nutr. 2005; 2(2): 38–44.
Asthma affects as many as 334 million people of all ages in all parts of the world.(1) This number continues to increase rapidly, and researchers believe this is due to a number of factors including increased air pollution and allergens, as well as obesity and dietary habits. In the UK, there are 5.4 million people with asthma (1.1 million children and 4.3 million adults), which means that asthma affects one in every 11 people.
It is reported that every ten seconds someone in the UK is having a potentially life-threatening asthma attack.(2) In the US, the number of adults who currently have asthma is 17.7 million and the number of children is 6.3 million.(3)
Asthma is a chronic inflammatory disease of the airways of the lungs and it is one of the most common chronic inflammatory disorders. It is characterised by recurrent attacks of breathlessness and wheezing, which vary in severity and frequency from person to person. Symptoms may occur several times in a day or perhaps several times per week in affected individuals. The triggers of asthma also vary and can include physical exercise, cold weather, hot weather, pollen, pollution or physical exercise. We don’t know what causes asthma and there is currently no known cure for asthma but most people with asthma who receive the right treatment find they can control their symptoms and lead normal lives. he most overwhelming symptom for most people that suffer from asthma is difficulty breathing, but it is not the only one. Asthma is often accompanied by a sensation of tightness in the chest, making you feel as if your chest is being squeezed, somewhat like a wide rubber band stretched tightly around the chest. Wheezing is also a symptom of asthma and coughing is also common which can become worse at night.
My youngest son has asthma and I see the effects of this chronic condition first hand. I remember when my son came downstairs one morning and he was having a real hard time breathing due to an asthma attack. This was a very scary situation as you can probably imagine. Sometimes, we underestimate how serious asthma is because it is generally controlled by mediation and inhalers. However, it is at times like this that we get a chilling reminder of just what this condition can do. To get a better understanding of asthma and its impact on health, we need to learn a little bit about how the lungs work. Let’s take a closer look.
How the Lungs Work
When you breathe in, you take in air. The lungs extract the oxygen from the air that is vital for every cell in our body. The oxygen is then passed into the blood and circulated around the body. Carbon dioxide is the waste product of this exchange and this is what we breathe out.
Figure 1.1 The lungs and the bronchial tree
Lets go into more detail on this amazing process that gives us the oxygen for life. In figure 1.1 above, we can see that when we take a breath the air travels down the windpipe (trachea). The trachea then branches into two sections, each one called a bronchus. The right bronchus goes to the right lung and the left bronchus goes to the left lung. Each bronchus then branches out into more bronchi (the plural for bronchus) and then these bronchi, in turn, branch out into smaller tubes called bronchioles. This trachea, bronchi and bronchiole structure is known as the bronchial tree, with the trachea as the trunk of the tree. The final branches, or the last bronchioles in the bronchial tree, are called the respiratory bronchioles, and these divide onto tiny openings called alveolar ducts. These microscopic tubes open into the alveoli, which is the plural for alveolus. There can be several alveoli coming off one duct so that they are clumped together.
It is in the alveoli that one of the most important processes that sustains all of life takes place – the gas exchange of oxygen and carbon dioxide. Oxygen is transported into the bloodstream by diffusing through the walls of the alveoli and into the capillaries. From here, the oxygen is carried around the body by a protein called haemoglobin in the red blood cells. This freshly oxygenated blood is carried from the lungs to the left side of the heart and pumped around the body. Once the oxygen has been used, the blood – now carrying waste products such as carbon dioxide – is carried back to the right side of the heart in the veins, where the waste products are then pumped into the lungs. The lungs will then remove the carbon dioxide through the alveoli, so that we can breathe out the carbon dioxide. Now that we know a little bit more about how the lungs work, we can move on to take a closer look at asthma.
Common Asthma Triggers
An asthma trigger is anything that can set off your asthma by irritating your sensitive airways. There are many asthma triggers and what sets off one person’s asthma symptoms can be different from someone else’s. For example, a high pollen count can trigger asthma symptoms in one person whereas cold weather will be a trigger in another person.
A person with asthma can have more than one trigger and at the same time. When this happens, there can be a stronger reaction and the asthma symptoms can be worse. Sometimes, a known asthma trigger won’t have much of an effect and this is because the sensitivity of the airways can vary on a day-to-day basis. If you have asthma, it is important to understand your triggers. In my son’s case, we know what that high pollen counts and freshly cut grass are particularly potent triggers; however, being around our lovable pet cat, who he adores, has no effect at all. The list below shows the most common asthma triggers.
Sometimes, a bit of detective work is required to identify what the triggers are, and it is a good idea to keep a diary of activities and symptoms if you suffer with asthma. This will help you identify any patterns and take action accordingly.
What Happens in Asthma?
Take, for example, a summer’s day and the pollen count is high. You may be out in the garden mowing the lawn – this is an irritant that can trigger asthma. The airways become inflamed and the muscles around the airways start to tighten up so that the airways become narrower. This is called bronchoconstriction. There can also be a build-up of mucus and the already narrowed airways become congested, making it harder to get air in and out of the lungs. Essentially, asthma is an immune response in the bronchial airways that is triggered by certain stimuli. In figure 1.2 below we can see the difference between a normal airway and the constricted, narrower airway of a person with asthma.
Figure 1.2 Normal airways and airways of a person with asthma
Asthma that is triggered by an allergen is known as allergic asthma, and this is the most understood of the factors that cause asthma. An estimated 80% of asthma patients have an allergy of some kind and, as mentioned previously, allergies have been increasing in recent years. Researchers are not entirely sure on the reasons for this rise, but it is thought that air pollution, antibiotics and dietary habits could be part of the reason. Studies show that children who grow up on farms – where they are exposed to more pollen, grass, dirt and bacteria – actually have fewer allergies than children growing up in cities.(4)
Essentially, a person with asthma has a susceptibility to environmental influences, such as allergens, and this can be made worse by exposure to a viral infection. This culminates in an inappropriate inflammatory response to allergens that are normally harmless. Activated T-cells have the capacity to control the amount and nature of inflammatory responses and research has shown that asthma patients have an increased level of Th2 cells or what is called Th2 dominance.
The Inflammatory Response in the Airways
The inflammatory response in the airways involves a complex interplay of the respiratory tract or epithelium, the innate immune system and the adaptive immune system. Chronic inflammation in asthma usually includes an increase in the number of activated Th2 cells. These cells produce the inflammatory cytokines which are responsible for IgE (immunoglobulin E) antibody production. White blood cells called eosinophils are released into the circulation and these are a rich source of leukotrienes, which contract the smooth muscle in the airways. It is these leukotrienes that are primarily responsible for the bronchoconstriction in asthma.
So now we have a number of reactions going on here in response to a stimulus such as an inhaled allergen. We have structural changes happening in the lungs as the walls of the airways become inflamed, we have increased mucus production by goblet cells and we have immune cells being activated to seek and destroy the foreign invaders. In addition, we have a number of ‘transcription factors’ involved in asthmatic inflammation. Transcription factors are proteins involved in the process of converting, or transcribing, DNA into RNA. As we know, DNA is the molecule that contains our genetic code – all of the information needed for our cells to do their jobs throughout our lives. However, these genes need to be copied through a process called ‘transcription’. The copy is called mRNA and it is this copy that is then turned into a gene product. However, not every gene needs to be expressed (or ‘switched on’) at the same time or in the same amount, and so gene expression needs to be controlled. This is the role of transcription factors. In asthma, these transcription factors act on genes to initiate the inflammatory cytokines and mediators that induce and perpetuate the inflammation involved in asthma.
Several years ago, it was discovered that a degree of inflammation is present in the bronchial tubes of people with asthma, even when they are feeling well with no symptoms. Now this inflammation may be so mild as to go unnoticed most of the time; however, this persistent and low-level inflammation makes the bronchial tubes more susceptible. The bronchial tubes are said to be ‘twitchy’ and more vulnerable to being triggered by stimuli such as allergens or the cold, for example. While the cause of asthma is not fully understood and a huge amount of research is going on in this area, chronic inflammation is thought to be a key factor in making the bronchial tubes twitchy.
Current Treatments for Asthma
Corticosteroids, which are often the treatments prescribed to manage asthma, modulate immune inflammatory responses in asthma by inhibiting the transcription factors listed above. In conjunction with corticosteroids, beta2-agonists are also used as effective bronchodilators.
These bronchodilators make breathing easier by relaxing the muscles in the lungs and widening the airways or bronchi. There are two types of bronchodilators called ‘short acting’ and ‘long acting’. The short acting bronchodilators are also known as relievers or rescue medication, and are used for acute asthma symptoms or sudden asthma attacks to open up the airways. The long acting bronchodilators are used to control longer term asthma symptoms, to reduce the ‘twitchiness’ of the bronchial tubes and make them less vulnerable to an inflammatory response that narrows the airways and produces mucus. That is why a person with asthma will take these medications every day, even when they feel well. Essentially, bronchial dilators control the systemic, low level inflammation that is present in the bronchial tubes.
It is not known how we can turn off this low level inflammation in the bronchial tubes, but there are a number of ways to reduce it. One method, of course, is through the long acting bronchodilator medication explained above. The other primary method is to avoid or reduce the exposure to triggers such as allergens, pollution, dust, pet dander and cold. However, that is easier said than done in today’s world where we are exposed to a myriad of pollutants and allergens every day. However, awareness is the first step to being able to make more informed decisions.
Can Food Have an Impact on Asthma?
Certainly, there are foods that are known to make asthma symptoms worse, such as shellfish, cow’s milk, eggs, yeast products and nuts. Just how much of an impact these foods have will vary from person to person; therefore, if you have asthma, it is important to monitor how these foods affect you.
By the same token, there are foods that can help to reduce the severity of asthma symptoms and improve lung function. Research shows that eating a diet rich in fruit and vegetables can help, which is really no surprise. Researchers hypothesised that the change in diet with westernisation may be responsible for the increase in asthma prevalence. Observations have shown that the consumption of foods rich in anti-oxidants (vitamin C, vitamin E, carotenoids, flavonoids, selenium and zinc) has decreased in countries such as the UK, while asthma prevalence has increased. Research has shown that diets rich in vitamin C, beta-carotene, magnesium and selenium are associated with a reduction in asthma prevalence and can potentially prevent or at least limit the inflammatory response in the airways.(5) In one study, adolescents with the lowest dietary intakes of anti-oxidant and anti-inflammatory micro-nutrients had lower lung function and increased respiratory symptoms, suggesting that adequate dietary intake may promote respiratory health and lessen the effects of oxidative stress.(6) In another study, researchers found symptomatic asthma in adults to be associated with a low intake of the dietary anti-oxidants vitamin C and manganese. The low intake of vitamin C appears to be primarily associated with a diet deficient in fruit.(7)
Recent epidemiological studies reported that a low incidence of asthma was significantly observed in a population with a high intake of flavonoids. Flavonoids possess anti-allergic activities that inhibit histamine and interleukin-4 and fruit and vegetables are high in flavonoids.(8)
Other dietary studies included a study of 598 Dutch school children ranging from 8 to 13 years old, which found that the risk of asthma was lessened by 54% in those that consumed wholegrains frequently and by 66% in those who consumed fish frequently.(9) In addition, diets high in the omega 6 fatty acids found in vegetable oils, margarines and farm raised meats has been associated with the increasing number of people with asthma. This increase in consumption of omega 6 fatty acids has coincided with a decrease in the consumption of saturated fats. There is also evidence showing a decrease in the consumption of oily fish, which contains omega 3.(10) This situation has led to the huge imbalance of omega 6 and omega 3 fatty acids, which is contributes to many inflammatory conditions.
Research has shown that adherence to the Mediterranean diet has a very beneficial effect on asthma and other allergies such as rhinitis. It was observed that for children in Crete, Greece, asthma and rhinitis were very rare and a study was conducted to see if this was attributed to the Mediterranean diet. They found that 80% of children ate fresh fruit at least twice a day and 68% ate vegetables twice a day.
These included grapes, oranges, apples and fresh tomatoes because these are the main local products in Crete. The results of the study showed that these foods were protective for wheezing and rhinitis. A high consumption of nuts was also found to be inversely associated with wheezing, whereas margarine increased the risk of both wheeze and allergic rhinitis. In conclusion, the results suggest that adherence to the Mediterranean diet, with fruits and vegetables eaten every day, had a beneficial effect on the symptoms of asthma and allergic rhinitis, and explains the relative lack of allergic symptoms in this population.(11)
Asthma is a complex disease that has many contributing factors including genetics, dietary habits, environmental toxins and lifestyle. It is clear to see from the research above that diet plays an important role in the development of asthma and also in reducing the symptoms of asthma. A healthy diet that is rich in fruit, vegetables, wholegrains and oily fish has been shown to reduce the symptoms of asthma and improve lung function. This is certainly food for thought, not just for those suffering from asthma but for everyone looking for healthier dietary habits. Are you getting your 5 a day?
For more information on asthma:
1. Global Asthma Network. The Global Asthma Report 2014. Vol 5.; 2014. doi:ISBN: 978-0-473-29125-9\r978-0-473-29126-6.
2.Asthma UK. Asthma UK | Asthma facts and statistics. https://www.asthma.org.uk/about/media/facts-and-statistics/.
3. CDC. FastStats - Asthma. https://www.cdc.gov/nchs/fastats/asthma.htm.
4. Sciences HH, Miller ME, Byington RP, et al. Exposure to Environmental Microorganisms and Childhood Asthma. N Engl J Med. 2011:2545-2559. doi:10.1056/NEJMoa1402685.
5. Kim J-H, Ellwood PE, Asher MI. Diet and asthma: looking back, moving forward. Respir Res. 2009;10:49. doi:10.1186/1465-9921-10-49.
6. Burns JS, Dockery DW, Neas LM, et al. Low dietary nutrient intakes and respiratory health in adolescents. Chest. 2007;132(1):238-245. doi:10.1378/chest.07-0038.
7. Patel BD, Welch AA, Bingham SA, et al. Dietary antioxidants and asthma in adults. Thorax. 2006;61(5):388-393. doi:10.1136/thx.2004.024935.
8. Kawai M, Hirano T, Higa S, et al. Flavonoids and related compounds as anti-allergic substances. Allergol Int. 2007;56(2):113-123. doi:10.2332/allergolint.R-06-135.
9. Tabak C, Wijga AH, De Meer G, Janssen NAH, Brunekreef B, Smit HA. Diet and asthma in Dutch school children (ISAAC-2) Topic collections Diet and asthma in Dutch school children (ISAAC-2). Thorax. 2006;61:1048-1053. doi:10.1136/thx.2005.043034.
10. Black PN, Sharpe S. Dietary fat and asthma: Is there a connection? Eur Respir J. 1997;10(1):6-12. doi:10.1183/09031936.97.10010006.
11. Chatzi L, Apostolaki G, Bibakis I, et al. Protective effect of fruits, vegetables and the Mediterranean diet on asthma and allergies among children in Crete. Thorax. 2007;62(8):677 LP-683. http://thorax.bmj.com/content/62/8/677.abstract.
There has been a lot of media attention on detox diets in recent years. One of the body’s major detoxification systems and very much the unsung hero is the lymph system, responsible for removing the waste from metabolic processes throughout the body. The lymphatic system plays a critically important role in our health and supports our immune, digestive, and nervous system to name a few. In this article, we take a closer look at the lymph system and how we can help it to work more efficiently.
We have twice as much lymph fluid as blood in our bodies and it is used to drain away waste products from our cells. Unlike our circulatory system that is powered by the most amazing pump in the Universe – our hearts, the lymph system relies on breathing and movement to move the lymph fluid along. If the lymph fluid stops, then we are in trouble!
The lymph system is made of a vast network of vessels that extend to every part of the body carrying lymph fluid. Lymph fluid contains infection fighting white blood cells that help to clear waste products and toxins. Along this network of vessels are between 600 hundred and 700 lymph nodes which act as filters cleaning the waste and toxins as they pass through. These lymph nodes are small oval structures that are in important part of our immune systems. In addition to this, we have lymphatic organs to help get rid of toxins, such as the tonsils, adenoids, spleen and thymus. The spleen is the largest lymphatic organ and is responsible for controlling the amount of red blood cells and blood storage in the body. When the spleen detects infection or micro-organisms in the body, it creates white bloods cells, called lymphocytes, along with the lymph nodes to fight the infection. The tonsils are a large cluster of lymphatic cells in the throat and are the body’s first line of defense against infection.
Another function of the lymph system is to return excess fluid to the circulatory system. The bloodstream transports oxygen and nutrients to the cells and to reach these cells, it leaves the small arteries and enters into the tissues. This fluid is known as interstitial fluid. When the cells have used the nutrients, 90% of this interstitial fluid returns in to the circulatory system. However, the remaining fluid needs to be removed including any metabolic waste and toxins produced by the cells. Over the course of a day, this can add up to about three litres of fluid!
We only have about five to six litres of blood so we need a mechanism to return this fluid into the circulatory system. This is where the lymph system steps in and is critically important to maintaining our blood volume. If the fluid remained in the tissue spaces, it would accumulate and lead to edema or swelling in certain parts of the body. The lymphatic capillaries, which are microscopic, collect fluid from the surrounding tissues. They carry this lymph fluid along with any metabolic waste created by the cells, and converge into larger lymphatic vessels which then subsequently converge into lymphatic trunks. The lymphatic vessels and trunks carry the lymph fluid up into the neck area and return the filtered and cleaned fluid to the bloodstream through one of two large ducts into the subclavian veins which carry both lymph and venous blood back to the heart.
So how does the lymph system work to get this lymph fluid up the body towards the neck? Amazingly, the lymph system does not have a pump! It depends on muscle contraction to move fluid. Muscles that line the lymphatic vessel wall contract rhythmically to move the fluid along. This is helped by muscle contraction throughout the body and also by deep breathing. Unlike the bloodstream which is a circulatory loop, the lymph system is a one way flow. Numerous valves in the vessels ensure that the fluid moves in one direction without any back-flow.
Can we improve our lymphatic circulatory system to help our bodies remove toxins? Yes, we need to look after our lymphatic circulatory system just as much as our blood circulatory system. The two are intrinsically linked. The lymphatic system drains away excess fluid from the tissues and removes waste products, toxins and antigens so it is also an intrinsic part of our immune system. If these drains becomes blocked for any reason, then poor health outcomes will follow. If the lymphatic system becomes clogged up with excessive toxins, the body will struggle to effectively remove these toxins and ultimately, the immune system will be compromised.
So what are the causes of a congested or sluggish lymphatic system?
How do we help the lymphatic system operate more efficiently and keep this incredibly important system in tip top shape?
Rebounding on a mini trampoline is reported to increase lymph flow by 15 to 30 times. The vertical up and down movement of rebounding is very effective at helping the lymph vessels ‘pump’ the lymph fluid up through the body by opening and closing the millions of one way valves throughout the system. Jumping on a re-bounder is very gentle on the joints and has many other benefits such as strengthening your muscles, improving your fitness as well as improving your balance.
NASA conducted a study on trampoline jumping which was published in the Journal of Applied Physiology in 1980. This study compared the difference between exercising on a treadmill and a trampoline. They concluded that for similar levels of heart rate and oxygen consumption, the magnitude of the bio-mechanical stimuli is greater with jumping on a trampoline than with running. So rebounding is an excellent way to not only get more exercise into your daily routine that won’t impact your joints, but also benefit our lymphatic system.
This is another beneficial exercise that works in a similar fashion to rebounding. Of course, this has more impact on the joints but only requires you to dig out that old skipping rope.
Dry Skin Brushing
Skin is your largest organ and absolutely critical to your good health. Dry skin brushing is another effective way to stimulate your lymphatic system and help you to detoxify your body. It will also improve the appearance of your skin by eliminating dead cells, encouraging regeneration and stimulating blood circulation.
You’ll need a natural bristle brush with a long handle for effective dry brushing. The brushing motion should be upwards following the direction of lymph fluid starting at the feet and working your way up to the heart area. For the best results, dry brush every morning for 5 to 10 minutes before showering.
There are many benefits to deep breathing but in this section we’ll focus on the how we can improve the efficiency of our lymph system by deep, diaphragmatic breathing. The expansion and contraction of the diaphragm stimulates the lymphatic system.
Deep, diaphragmatic breathing or ‘abdominal breathing’ is the key to this process and 10 minutes a day will oxygenate the blood and get the lymph fluid flowing. Most people breath with the chest. What I mean by this is that, typically, when you breathe in, you’ll open the chest up and maybe even pull your stomach in. When you exhale, the stomach goes out and the chest deflates. This shallow type of breathing is known as paradoxical breathing. Think of it as breathing backwards.
Abdominal breathing turns this around so that we are breathing correctly. So how do we do this? Breath in deeply and slowly through the nose letting your belly fill as you inhale. This should be a natural movement and not forced. Then breath out slowly letting your abdominal push the air out. What this does is change the intra-abdominal pressure as we go from inhale to exhale. This creates a vacuum which helps to pump lymph fluid up through the body to the thoracic ducts where it reconnects with the venous system.
Drinking adequate amounts of water has many health benefits, but is it really important to the lymphatic system? Can we literally ‘flush out’ our toxins by drinking more water? To get a view on how important water is for our bodies we only need to look at what happens when we don’t get any! The adult human body is made up of between 60 and 70% water, depending on age. Of this water, only around 20% is blood.
As we discussed earlier, there is twice as much lymph fluid than blood in the body so a large percentage of our water is in the lymphatic system. Indeed, the word lymph comes from the Latin ‘lympha’ which means ‘clear spring water’. Chronic dehydration can slow and stagnate the flow of lymph. Therefore, it makes sense to ensure we are getting enough high quality water to help the lymph system and all of our internal systems work optimally.
The lymphatic system needs a relaxed body to work optimally. If we are stressed out and up tight, then it is easy to see why our internal systems slow down. Excessive stress is a major cause of many illnesses and it can certainly have a negative impact on the lymphatic system. During a stress response, the muscles to tighten which prepares a person to fight or flight.
Chronic stress leads to chronic tension in the muscles and stiff, aching neck, shoulder and back muscles are common symptoms of this condition. With all of this tension in the muscles, the tiny lymphatic vessels are being constricted so that lymph flow is reduced or even stopped in certain parts of the body. This means that the cells will not be able to get rid of their metabolic waste which can lead to toxicity. Think of it like this, if we keep putting our household rubbish out near the bin, but the refuse collection does not take our rubbish away, we get a build up of rubbish which starts to rot and becomes toxic. Not a pleasant environment to live in! When the lymph flow stops and our metabolic waste is not being collected, our cells are bathing in toxic waste. This is equally unpleasant for our health. In addition, chronic stress is releasing additional chemicals in to the bloodstream that we need to eliminate from the body. This puts more strain on our already overloaded systems.
Therefore, managing our stress levels is critically important to our lymphatic system as well as all of our internal systems. There are many ways in which we can manage our stress levels and we will be discussing this in more detail later in the book.
Otherwise known as manual lymphatic drainage (MLD), this is another method to get a sluggish lymphatic system moving again. MLD is often an important part of lymphoedema treatment to help stimulate lymph flow. It is a specialist massage technique that is offered from qualified MLD specialists. It involves a very light pressure combined with soft pumping movements in the direction of the lymph vessels and nodes. There is a simplified version that you can learn to do at home called simple lymphatic drainage (SLD), however, it is important to learn these skills from a specialist and also advisable to consult with your doctor before considering this.
In this article, we've learned that the lymphatic system plays a critically important role in our health by removing waste products from metabolic processes. It is certainly the unsung hero that helps to detox our bodies, working behind the scenes 24/7. However, if we don't look after our lymphatic system, it can slow down and become sluggish, which may result in the immune system being compromised. Maybe its time to start rebounding!
In this article, we take a look at three popular diets: The 5:2 diet, the Paleo diet and the Dukan diet. These diets all restrict calories in some way and they all work. But are these diets healthy for you or do they result in nutritional deficiencies? In addition, are these diets suitable for a people involved in sports? Lets take a closer look.
5:2 Fast Diet
The 5:2 diet, also known as The Fast Diet, is currently the most popular intermittent fasting diet.
It was popularized by British doctor and journalist Michael Mosley. It’s called the 5:2 diet because five days of the week are normal eating days, while the other two restrict calories to 500–600 per day. This diet is not prescriptive about what food to eat but rather, when to eat those foods.
The Principles Behind the Diet
The 5:2 diet is based on a principle known as intermittent fasting (IF). For five days a week, you eat normally and don’t have to think about restricting calories. On the other 2 days, you reduce calorie intake to 500 calories per day, for women and 600 calories per day for men. You can choose how to order the fasting days as long as there is a non-fasting day in between. Eating normally means eating a healthy, balanced diet and not eating literally anything.
There are very few studies that have tested the 5:2 diet specifically and many more studies on intermittent fasting as a whole. One study showed that the 5:2 diet caused weight loss similar to regular calorie restriction. Additionally, the diet was very effective at reducing insulin levels and improving insulin sensitivity (1).
A similar diet, the 4:3 diet was shown to help reduce insulin resistance, asthma, seasonal allergies, heart arrhythmias and menopausal hot flushes. (2,3). In a randomized controlled trial which included both normal weight and overweight individuals showed major improvements in the group doing 4:3 fasting, compared to the control group that ate normally (4).
After 12 weeks, the fasting group had:
The results of this study show that intermittent fasting has some impressive health benefits as well as the ability to reduce weight.
Research shows that intermittent fasting causes a smaller reduction in muscle mass than weight loss with conventional calorie restriction. A review was conducted to examine the effects of a calorie restriction diet versus intermittent fasting diet on weight loss, fat mass loss and lean mass retention in overweight and obese adults. The results showed that similar weight loss and fat mass loss with 3 to 12 weeks' intermittent fasting and daily calorie restriction. In contrast, less fat free mass was lost in response to intermittent fasting versus daily calorie restriction. These findings suggest that these diets are equally as effective in decreasing body weight and fat mass, although intermittent fasting may be more effective for the retention of lean mass.(5)
The Bottom Line
The 5:2 diet may have several impressive health benefits. These include weight loss, reduced insulin resistance and decreased inflammation. Blood lipids may also be improved. For losing weight, the 5:2 diet appears to be effective when done correctly. Results are dependent on eating a healthy, balanced diet on non-fasting days rather just eating anything. Therefore, it is very important not to compensate for the fasting days by eating much more on the non-fasting days.
The downside of this diet is that there is a drastic calorie restriction on 2 days a week and if these calories are not consumed wisely, nutritional deficiencies could result. In addition, such restricted calorie intake can make you feel dizzy, irritable, give you headaches and make it hard to concentrate, which can affect work and other daily tasks. Other reported side effects are difficulties sleeping and daytime sleepiness, bad breath and dehydration. I can also see that there would be a tendency to compensate and overeat on the non-fasting days.
The 5:2 Diet for the Sports Person
The principles of modulating macro nutrients makes sense, however, this diet takes this to an extreme and in my view, it is not a suitable diet for anyone involved in an intense training routine. The 5:2 diet provides no guidance on macro nutrient balance and with only 500 to 600 calories on fasting days, there is not a lot of room for manoeuvre. Personally, 500 to 600 calories a day would not provide enough energy to support my training and recovery.
The fasting days would not provide enough protein, carbohydrates or micro nutrients to support high intensity training. With such a low level of calories and nutrients on the fasting days, there is a possibility of feeling faint and weak which is clearly not conducent to optimal training. I also see the lack of calories and potential lack of nutrients on the fasting days as a major challenge for sustainability.
The Paleo Diet
The paleo diet emulates the diet of our hunter-gatherer ancestors, based on the premise that they did not suffer from the same diseases as modern humans. In the year 2013, the paleo diet was the world’s most popular diet. However, it is still very controversial among health professionals and mainstream nutrition organizations.
The Principles Behind the Diet
The core of paleo is the diet is that it bans the consumption grains, sugars, and modern vegetable oils in favour of high-quality meat, fish, eggs, and vegetables. Basically, the paleo diet suggests that if it looks like it was made in a factory, don’t eat it!
Several studies suggest that this diet can lead to significant weight loss (without calorie counting) and major improvements in health. In one study 29 men with heart disease and elevated blood sugars or type 2 diabetes, were randomized to either a Palaeolithic diet or a Mediterranean-like diet. Neither group was calorie restricted. This study was conducted over 2 weeks and measured glucose tolerance, insulin levels, weight and waist circumference.
The results show that the group on the paleo diet group saw a significant improvement in glucose tolerance. The glucose tolerance test measures how quickly glucose is cleared from the blood. It is a marker for insulin resistance and diabetes. Those on the Mediterranean Diet did not did not see a significant improvement in glucose tolerance. Both groups lost a significant amount of weight. The paleo group lost 11lbs and the control group lost 8.4 lbs. However, the difference was not statistically significant between groups. There was a statistically significant reduction in waist circumference in the paleo diet group (2.2 inches) compared to the control group (1.1 inches).
Every patient in the paleo group ended up having normal blood sugars, compared to 7 of 15 patients in the control group. The paleo group ended up eating 451 fewer calories per day (1344 compared to 1795) without intentionally restricting calories or portions. In conclusion, a Palaeolithic diet lead to greater improvements in waist circumference and glycemic control, compared to a Mediterranean-like diet.(6)
In another study 13 individuals with type 2 diabetes were placed on either a Palaeolithic diet or a typical Diabetes diet in a cross-over study. They were on each diet for 3 months at a time. On the paleo diet, the participants lost 6.6 lbs more weight and lost 1.6 inches more off of their waistlines, compared to the Diabetes diet. HbA1c was measured, which is a marker for 3-month blood sugar levels. This decreased by 0.4% more on the paleo diet. HDL increased by 3 mg/dL on the paleo diet compared to the Diabetes diet. Triglycerides went down by 35 mg/dL on the paleo diet compared to the Diabetes diet. In conclusion, over a 3-month study period, a Palaeolithic diet improved glycemic control and several cardiovascular risk factors compared to a Diabetes diet in patients with type 2 diabetes. (7)
A study was conducted with 10 healthy women with a BMI over 27, They consumed a modified Palaeolithic diet for 5 weeks and measurements for weight loss, liver fat, muscle cell fat and insulin sensitivity were taken. The results showed that the women lost an average of 9.9 lbs and reduced their waist circumference by 3.1 inches. The fat content of liver and muscle cells are a risk factor for metabolic disease and the results of this study showed a reduction in liver fat of 49%, but no significant effect on the fat content of muscle cells. The women who had a lot of liver fat at the baseline had the most significant decrease. In addition, blood pressure went down from an average of 125/82 mmHg to 115/75 mmHg, although it was only statistically significant for diastolic blood pressure (the lower number). Total cholesterol decreased by 33 mg/dL and Triglycerides went down by 35 mg/dL. In conclusion, during the 5 week trial, the women lost weight and had major reductions in liver fat. They also had improvements in several important health markers.(8)
The studies had statistically significant reductions in waist circumference, which should translate to a reduced risk of diseases like diabetes and cardiovascular disease. The limitation of these studies are that they were short term and based on few participants. Longer term studies are required and a greater number of people.
The Bottom Line
The good thing about the paleo diet is that encourages you to eat less processed food and more fruit and vegetables. This diet is also simple and doesn’t involve counting calories. On the downside, this diet bans the consumption of dairy and wholegrain foods which form part of a healthy, balanced diet. It is a high protein diet with a lot of meat and not a lot of complex carbohydrates which,
in my view for a sports person, is not an optimum diet. In addition, this diet is based on a lot of assumptions made about our ancestor’s diets from the Palaeolithic era and the lack of disease that we see in modern society. I think we need to remember that our Palaeolithic ancestors had a much shorter life expectancy than we enjoy today. Palaeolithic skeletons indicated a life expectancy of 35.4 years for men and 30.0 years for women! Having said that, the research above does show some compelling evidence that the paleo diet has a beneficial effect on several health markers.
The Paleo Diet for the Sports Person
While some of the principles of the paleo make sense for the sports person such as avoiding processed foods, eating more fruit and vegetables etc., my personal view is that there are not enough complex carbohydrates in the diet to provide the necessary energy for intense training. In addition, it seems that there is a potentially a lot of saturated fat in this diet from the consumption of larger amounts of meat.
Once again, calories are not counted in this diet and therefore, you don’t know where you stand with your macro nutrient breakdown, other than you are eating a fair bit of protein and fat. The exclusion of grains and dairy foods groups also limits micro-nutrients from these important food groups that are a good source of calcium and vitamin B complex for example.
Due to the low carbohydrate intake, the body must shift to a process called ketosis. This is a normal metabolic process under certain circumstances. When the body doesn't have enough carbohydrates to use for its energy requirement, it must burn fat for energy. As part of this process, it makes ketones. Ketosis can become dangerous when ketones build up. High levels lead to dehydration and change the chemical balance of your blood. You will also feel pretty lousy during the transition. This has come to be known as ‘Low-Carb Flu’. Some people experience lethargy, fatigue, irritability and shakiness when first eliminating starches, grains and legumes from their diet. The low-carb flu symptoms usually last up to a month and during this time as the body transitions to burning fats as a fuel source instead of carbohydrates. This is not a good scenario for a sports person engaged in intense training and I see this as a major challenge for sustainability. In addition, as the brain also uses glucose as its primary fuel source, depriving oneself of the very foods that provide this energy does not make a lot of sense.
The Dukan Diet
The Dukan Diet was created by Dr. Pierre Dukan, a French general practitioner who specializes in weight management. Dr. Dukan published the book, The Dukan Diet in 2000. This diet has reportedly helped people achieve rapid, easy weight loss without hunger.
The Principles Behind The Diet
The Dukan diet is a low-carb, high-protein diet that is split in to 4 phases. There is no limit to how much you can eat during the plan's four phases, provided you stick to the rules of the plan. The four phases are as follows:
Phase 1 - Attack phase (1-7 days): You start the diet by eating unlimited lean protein plus 1.5 tablespoons of oat bran per day.
Phase 2 - Cruise phase (1-12 months): Alternate lean protein one day with lean protein and non-starchy vegetables the next, plus 2 tablespoons of oat bran every day.
Phase 3 - Consolidation phase (variable): Unlimited lean protein and vegetables, some carbs and fats, one day of lean protein only per week, and 2.5 tablespoons of oat bran per day. You should do this for 5 days for every pound lost in phases 1 and 2.
Phase 4 - Stabilization phase (indefinite): This is the final phase and follows basic Consolidation phase guidelines, but rules can be loosened as long as weight remains stable. Oat bran is increased to 3 tablespoons per day. This phase is all about maintaining the improvements achieved during the earlier phases of the diet. No foods are strictly off-limits.
There is very little research specifically on this diet. However, there is one study on Polish women who followed the Dukan Diet. These women ate about 1,000 calories and 100 grams of protein per day and lost 33 pounds in 8–10 weeks. (9)
The Bottom Line
In summary, the Dukan Diet allows protein-rich foods in Phase 1 and protein with vegetables in Phase 2. It adds limited portions of carbs and fats in Phase 3, with looser guidelines in the final phase. The aim is gradual weight loss of up to 2lb a week and to promote long-term weight management. There's no time limit to the final phase, which involves having a protein-only day once a week and taking regular exercise. The high-protein Dukan Diet can produce fast weight loss and losing weight quickly can be motivating. However, it seems a very unbalanced and unhealthy diet, particularly in the early phases. The Dukan Diet is different from many related high-protein diets in that it restricts both carbs and fat. It is a high-protein, low-carb and low-fat diet.
The Dukan Diet for the Sports Person
Once again, this diet is low in complex carbohydrates that would not provide the necessary energy for intense training. Calories are not counted in this diet and therefore, you don’t know where you stand with your macro nutrient breakdown, other than you are eating a lot of protein and low carbs as well as low fat.
As so many food groups are excluded from this diet in the early phases, there is the possibility of nutrient deficiency in the early stages. In fact, the diet recommends taking a multi-vitamin to compensate for this.
In a similar fashion to the Paleo Diet, the body must shift to the process of ketosis to burn fat for its energy requirement. Once again, during this transition, you will feel pretty lousy and feel the effects of the so called ‘Low-Carb Flu’ with lethargy, fatigue and irritability. This is not a good scenario for a sports person engaged in intense training. I see this as a major challenge for sustainability. In addition, as the brain also uses glucose as its primary fuel source, depriving oneself of the very foods that provide this energy does not make a lot of sense. I view this diet as unhealthy and it is certainly not a diet that would support an endurance athlete or indeed someone engaged in an anaerobic sport in their training.
Comparison of The 3 Diets
These diets all restrict calories in some way, otherwise, they wouldn’t work. However, the macro-nutrient composition of the Paleo and Dukan diet are simply not balanced for the sports person and the lack of complex carbs will be a real issue when it comes to energy requirements. The 5:3 diet seems a little better in that it is not restricting a particular macronutrient and therefore, this can be modulated based on your sport. However, my concern on this diet is simply the lack of calories on the fasting days which will impact training and recovery. Macronutrients can be determined on the fasting days but there is very little room for manoeuvre with only 500-600 calories. In summary, I would not recommend any of these diets for a sports person.
1. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women.
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2. The effect on health of alternate day calorie restriction: eating less and more than needed on alternate days prolongs life.
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3. Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma.
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4. Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial.
Nutr J. 2013 Nov 12;12(1):146. doi: 10.1186/1475-2891-12-146.
5. Intermittent versus daily calorie restriction: which diet regimen is more effective for weight loss?
Obes Rev. 2011 Jul;12(7):e593-601. doi: 10.1111/j.1467-789X.2011.00873.x. Epub 2011 Mar 17.
6. A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease.
Diabetologia. 2007 Sep;50(9):1795-807. Epub 2007 Jun 22.
7. Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study.
Cardiovasc Diabetol. 2009 Jul 16;8:35. doi: 10.1186/1475-2840-8-35.
8. A Palaeolithic-type diet causes strong tissue-specific effects on ectopic fat deposition in obese postmenopausal women.
J Intern Med. 2013 Jul;274(1):67-76. doi: 10.1111/joim.12048. Epub 2013 Mar 11.
9. Assessment of food intakes for women adopting the high protein Dukan diet.
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Obesity is an increasingly common, yet preventable condition, that is associated with an increased risk of type 2 diabetes and cardiovascular disease. The research shows that the global epidemic of obesity is caused by the over-consumption of high fat, energy dense diets and a sedentary lifestyle. Genetics also play a role in determining how susceptible people are to weight gain but essentially, obesity is the result of an energy intake that exceeds energy expenditure over a protracted period of time. In a nutshell, obesity is generally caused by eating too much and moving too little.
If you consume high amounts of energy, particularly fat and sugars, but don't burn off the energy through exercise and physical activity, much of the surplus energy will be stored by the body as fat. Lets take a closer look.
The average physically active man needs about 2,500 calories a day to maintain a healthy weight, and the average physically active woman needs about 2,000 calories a day. By consuming foods that are high in fat, refined carbs and sugar, we can easily blast right through this amount of calories. For example, eating a large takeaway hamburger, fries and a milkshake can total 1,500 calories – and that's just one meal! There is also very little nutrition in fast foods and junk foods so they are empty calories.
Obesity doesn't happen overnight. It develops gradually over time, as a result of poor diet and lifestyle choices. Here are some other dietary factors that contribute to obesity:
So there are lots of ways to consume more calories than we need on a daily basis. The other side of the equation is exercise. Many people aren't physically active, so a lot of the calories they consume end up being stored in their body as fat.
Lack of Physical Activity
Lack of physical activity is another important factor related to obesity. Many people have sedentary jobs these days that involves sitting at a desk for most of the day. They may also drive to work or take the bus or train. When they get home, they are tired and tend to watch TV to relax, surf the Internet, consume social media and so on. People often say that they don't have time to be physically active because of long work hours and time spent commuting. Basically, not doing much exercise means they are not burning calories and also, they are not stimulating their metabolism.
In some cases, underlying medical conditions may contribute to weight gain. These include:
However, if conditions such as these are properly diagnosed and treated, they should pose less of a barrier to weight loss.
Fat Loss Diet
First off, I would recommend that a person wanting to lose body fat determines their body composition. This can be achieved using body fat callipers, hydrostatic weighing or even a DEXA scan. The dieting process will be a gradual process and the length of time will depend on the amount of weight a person wants to lose.
We will avoid crash diets, starvation diets and fad diets as these often end up in muscle loss too which subsequently leads to a drop in the Basal Metabolic Rate (BMR) which is not good when you want to lose bodyfat. We will be targeting fat loss in this plan. For example, if a person weighs 195 pounds with 20% body fat with a lean body mass of 156 pounds, we are targeting a reduction of 4 calories per pound of lean body mass.
This equates to 625 calories per day. With 3,000 calories per day nutrition plan, we are looking at 2,375 calories a day on this diet plan. A pound of fat contains 3,500 calories so it will take about 6 days to lose a pound of fat. We want to avoid losing fat at a faster rate so as to avoid losing muscle mass too. Using this approach, a person will lose around 5 pounds of fat per month. I would recommend that these calories are reduced evenly from each meal and that this reduction should come from simple carbs and fat. For example, the calorie reduction should come from cutting back on high fat foods, pastries, biscuits, sugary drinks and refined carbs such as white bread and white pasta.
Physical activity increases energy expenditure and also reduces the risk of heart disease more than that achieved by weight loss alone.
Exercise also has a significant effect on the metabolism. Exercise increases the metabolic rate and this helps to control bodyweight by regulating the amount of calories being burned on a daily basis. However, different types of exercise influence the metabolic rate in different ways. Low intensity aerobic exercise will have the least impact on metabolic rate. High intensity cardio exercise has more effect on the metabolic rate and this involves shorter periods of high intensity exercise.
The best exercises for increasing the metabolic rate are weight training and high intensity interval training. During the training itself, the calorie burn will not be that high but the effect on the metabolic rate lasts longer after the training is finished.
Exercise science has come a long way in the last decade and research shows that traditional cardio does not provide the benefits once thought. Clearly, any exercise is better than none but there are more efficient ways of training to achieve the results we want. Studies have shown that short burst training can help to burn fat and increase fitness levels even after 15 or 20 minutes of exercise. A study published in April 2016, investigated whether sprint interval training (SIT) could improve insulin sensitivity and other measures of cardio-metabolic health to the same extent as traditional moderate-intensity continuous training (MICT). SIT involved 1 minute of intense exercise within a 10-minute time commitment, whereas MICT involved 50 minutes of continuous exercise per session.(1)
In this randomised controlled trial, sedentary men performed three weekly sessions of sprint interval training or moderate intensity training for 12 weeks or served as non-training controls. The sprint interval training involved 3 x 20 second ‘all-out’ cycle sprints interspersed with 2 minutes of cycling at a lower level. The moderate intensity training involved 45 minutes of continuous cycling at 70% maximal heart rate. Both protocols involved a 2-minute warm-up and 3-minute cool-down period. The results showed that twelve weeks of brief intense interval exercise improved indices of cardio-metabolic health to the same extent as traditional endurance training in sedentary men, despite a five-fold lower exercise volume and time commitment.
In summary, obesity is basically the result of an energy intake that exceeds energy expenditure over a protracted period of time. In a nutshell, obesity is generally caused by eating too much and moving too little. The good news is that we can combat increases in bodyfat with a healthy diet and fewer calories in conjunction with an exercise routine that increases the metabolism and burns more calories. In the next articles in this series, we'll take a closer look at 3 of the popular diets out there to see how they stack up.
1. Twelve Weeks of Sprint Interval Training Improves Indices of Cardiometabolic Health Similar to Traditional Endurance Training despite a Five-Fold Lower Exercise Volume and Time Commitment. PLoS One. 2016;11(4):e0154075. doi:10.1371/journal.pone.0154075.
Sports & fitness nutritionist, researcher and author on a mission to improve the human condition. Focusing on evidence-based and outcome-based nutrition, training, mindset & environment