19. Diets and Nutrition for Health and Fitness

This section looks at diets and nutrition for a healthy life and for fitness as well as examining the claims about detox, anti-oxidants, organic and GM food, e numbers and much more. It will contain the following sections:

Supplements have their own section which follows this one.

If you wish to go directly to one of the topics above, click on the blue underlined title.

Diets for Health

As well as the many diets to help weight loss, there are thousands that claim to offer a healthier, disease-free life. Some diets are for people with specific problems such as a gluten-free diet for those with coeliac disease and a diet for diabetics. I shall not go into any detail about diets for people with specific medical conditions.

Vegetarian and even vegan diets have increased greatly in popularity in recent years. Sometimes they are advocated as a healthier alternative to meat or animal-based products. Sometimes they are claimed to be better for the environment as it takes less energy to produce food of a certain calorific value. A vegetarian diet excludes meat although some people will still eat fish including shellfish. A vegan diet excludes all animal products including milk and eggs.

Stop eating the rubbish.
Start eating proper food.
Eat a wide variety of foods.

In a prospective cohort study in the UK, fish eaters and vegetarians had lower rates of coronary heart disease than meat eaters, although vegetarians had higher rates of stroke.1Risks of ischaemic heart disease and stroke in meat eaters, fish eaters, and vegetarians This was another part of the EPIC (European Prospective Investigation into Cancer) trial. Researchers followed 48,188 middle-aged adults without any history of heart attacks or strokes for about 18 years. Over the time of follow up, there were, 2,820 cases of coronary heart disease and 1,072 cases of stroke of which 300 were from haemorrhage. After adjusting for various factors that would cause bias, they found that fish eaters and vegetarians had a lower rates of coronary heart disease than meat eaters. Vegetarians, including vegans, were 22% less likely to develop coronary artery disease than meat eaters. This is the equivalent of 10 fewer cases of coronary artery disease per 1,000 people over a decade among vegetarians compared to meat eaters, researchers calculated. However, that was not all of the story.

By contrast, vegetarians had 20% higher rates of total stroke than meat eaters, equivalent to three more cases of total stroke per 1,000 population over 10 years, mostly due to a higher rate of brain haemorrhage. Although the reduced risk of coronary heart disease in non-meat eaters may outweigh the risk of stroke about three-fold, people seem to be very much more afraid of stroke than heart disease. Vegans are also at 40% greater risk of fracture due to osteoporosis.2Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study Diet experts said, whatever people’s dietary choice, eating a wide range of foods was best for their health.

Keep processed food to a minimum

An article in The Times was called 3Healthy? Just because it’s vegan, doesn’t mean it’s good for you It was scathing about many of the supermarket options for supposedly healthy vegetarian or vegan diets, noting that when a nutritionist tried a variety of supermarket vegan options, she found that many of the products were high in fats, salts, sugar and preservatives, while some had virtually no nutritional value. Not all of the 24 items examined were disasters, but many had much processed content and high levels of salt and fat. High levels of salt may account for the finding of a raised risk of stroke, especially haemorrhagic stroke, in vegetarians.

About 1% of the population has coeliac disease and so they must abide by a gluten-free diet for health. However, the level of sales of gluten-free products suggest that around 6% of the population eat gluten-free food. Some people choose a gluten-free diet because they believe that it is a healthier option. A double-blind placebo-controlled randomised controlled trial found that giving gluten to healthy volunteers did not produce any symptoms.4Gluten Does Not Induce Gastrointestinal Symptoms in Healthy Volunteers However, it was interesting to note that when they screened their volunteers before the trial, they found two who had undiagnosed coeliac disease. If you genuinely think that you feel unwell with gluten, get yourself checked. The low gluten diet had an adverse effect on the gut biome, especially with regard to Bifidobacterium.5A low-gluten diet induces changes in the intestinal microbiome of healthy Danish adults There may be less fermentation in the gut and this may improve bloating. However, as noted in Further Resources, any benefit is thought to be purely placebo.

In coeliac disease, allergy to gluten leads to shortening of the villi in the small intestine, leading to poor absorption of food, diarrhoea and malnutrition

A study of long-term gluten consumption in adults without coeliac disease found that long-term dietary intake of gluten was not associated with any difference in risk of coronary heart disease.6Long term gluten consumption in adults without celiac disease and risk of coronary heart disease (Note that the Americans spell coeliac without an e). However, the avoidance of gluten may result in reduced consumption of beneficial whole grains, which may affect cardiovascular risk. The promotion of gluten-free diets among people without coeliac disease should not be encouraged.

A gluten-free diet may not be as innocuous as many would believe. An American study found that subjects on a gluten-free diet had significantly higher urine levels of arsenic and blood levels of mercury, lead, and cadmium than those not avoiding gluten.7Accumulation of Heavy Metals in People on a Gluten-Free Diet Although the levels were below those normally regarded as toxic, they were sufficiently higher than normal to cause concern.

Dermatitis herpetiformis responds to a gluten free diet but it is very rare

As well as coeliac disease, there is one other disease in which a gluten free diet will provide a cure. This is called dermatitis herpetiformis. It is a very rare disease where bullae, like large blisters, appear on the skin. About 1% of the population have coeliac disease but in all my years and experience of clinical practice, I have never seen a case of dermatitis herpetiformis.

If you are looking for a healthy diet and you do not have any disease that may affect what you should eat, have a varied diet. Go for a variety of colours too as this is likely to increase your intake of certain vitamins and minerals that may otherwise be lacking. Do not exclude whole ranges of food such as fat or carbohydrates. Eat plenty of roughage and fruit and vegetables. Avoid added salt or sugar. Keep highly processed foods to a minimum.

Diet for Mental Health

Research from Australia shows that a simple dietary intervention that emphasizes lean meat, fish, and fresh fruits and vegetables appears to improve depressive symptoms within 3 weeks in young adults with unhealthy eating habits.8A Prospective Study of Diet Quality and Mental Health in Adolescents They do not recommend stopping medication or other therapies. Eating less processed foods appeared to correlate more strongly with improved depression scores than other elements of the diet, although it is difficult decide if eliminating processed foods alone would be enough to reduce depression. This was only a small trial but it is quite possible that improving diet to improve the gut biome can have a significant effect on depression.

Diet affects the brain

A more recent review was called 9Towards improving mental health by what you eat. It found a strong link between vitamin B12 deficiency and an increased risk of fatigue, depression, and memory problems. However, unless there is a specific disease called pernicious anaemia or another cause for failure to absorb vitamin B12, dietary deficiency is rare except in vegans, but this seems to be the latest fad. They found that there is increasing evidence of a link between a poor diet and the worsening of mood disorders, including anxiety and depression. The review showed there are “strong correlations” between a healthy diet and better mental health, especially with increased consumption of fresh fruits and vegetables.

A healthy diet for a healthy brain

The health benefits of certain specific foods were not supported by evidence. The role of vitamin D supplementation has shown conflicting results. An increase in the quantity of refined sugar in the diet seems to increase ADHD and hyperactivity, whereas eating more fresh fruit and vegetables seems to protect against these conditions. Nutritional interventions for autism have not been subjected to sufficient analysis. Hence, there are no specific foods for specific conditions, but a good, varied diet with fibre and vitamins, has a beneficial effect on mental as well as physical health.

Obesity is also linked to depression in children and from the age of seven, mental health and obesity appear to be entwined and exacerbate each other.10Obesity and depression ‘hand-in-hand’ in children The importance of bacteria in the gut, called the biome, has been noted in the earlier chapter Basics of Nutrition. The abysmal diet, so often seen in adolescence is associated with both obesity and depression. A review called 11Microbiome and Mental Health, Specifically as It Relates to Adolescents suggested that the poor diets that are so common among adolescents may contribute to the rise in depression in this age group.

As well as looking at the effect of diet on mental health, there is increasing evidence about the effect of mental health on physical health. An interesting article based on a Danish national registry found that people with mental disorders had an increased risk of certain physical disorders too.12Association between Mental Disorders and Subsequent Medical Conditions Some results were unsurprising, such as the four-fold increase in risk of gut or liver disorders in men with alcohol abuse. They also found that women with anxiety disorders had a 50% greater chance of heart disease or stroke over the next 15 years. The researchers estimated associations between 90 pairs of mental disorders and broad-category medical conditions, as well as 310 pairs of mental disorders and specific medical conditions. Schizophrenia was associated with a reduced risk of developing musculoskeletal conditions. One of the authors said that many people with mental disorders have an unhealthy lifestyle, including low exercise, poor diet, smoking, and alcohol, which may account for the increased risk of physical illness. Furthermore, they may not seek appropriate treatment for their health conditions. Most mental disorders were associated with an increased risk of a subsequent medical condition. For years we have associated anxiety with heart attacks and strokes. It seems this is correct.

It is easy to explain the increase in physical illness in people with mental health problems as being related to poor lifestyles but there is more too it. Anxiety and worry increase the background levels of inflammation and this has an adverse effect on arterial disease leading to coronary artery disease and stroke and possibly cancer and degenerative diseases such as dementia. Even the inflammation of poor dental hygiene can have a bad effect on the coronary arteries.13Dental disease and risk of coronary heart disease and mortality A mediator of inflammation and the immune system which we found was overactive in COVID-19. What You Need to Know is cytokines. A cytokine storm leads to the lung problems and organ failure in the disease. Cytokines are well recognised mediators of disease.14Cytokines and Disease Mediators The immune system can have an effect on the brain.15From Inflammation to Sickness and Depression: When the Immune System Subjugates the Brain An interesting article called 16Worry, Anxiety Tied to Increased Inflammation shows that psychological stress is bad for health. The body and mind are intimately related.


Salt raises blood pressure even if it is normal

The correlation between a high salt consumption and hypertension (high blood pressure) has been well known for many years. Therefore, to look for evidence, instead of searching for individual papers, I searched for “salt and hypertension” on the Cochrane website http://www.cochrane.org/. It gave several different reviews, examining different aspects such as a low salt diet for preventing hypertension in pregnancy. I have chosen 17 Modest salt reduction lowers blood pressure in all ethnic groups at all levels of blood pressure without adverse consequences. They found that reducing salt intake reduced blood pressure in all races and in people with or without hypertension. They said that public health recommendations in most countries are to reduce salt intake from the current levels of approximately 9 to 12 grams per day to less than 5 to 6 grams per day. However, a further reduction to 3 grams per day will lower blood pressure more. Therefore, 3 grams per day should become the long-term target for population salt intake.

Sea salt is still basically salt

Sometimes sea salt is advertised as being a healthy option. Sea salt, like any other salt used in cooking or as a condiment, is mostly sodium chloride and so will have the same effect on blood pressure. Sea salt contains iodine, and this is essential for the thyroid gland. Deficiency can cause an inadequate production of the thyroid hormones. In the past, this has been seen in Derbyshire and Switzerland where the soil is low in iodine, but anyone who eats sea fish at least once a week, should have little difficulty in keeping adequate levels of iodine. Basically, salt is salt. As salt is sodium chloride, you may see salt referred to as “sodium”.

An attempt to make salt look healthy. Organic salt is nonsense. It is an inorganic chemical

It is impossible to have food without some salt in it and this is required, especially if doing exercise in a hot environment which will induce profuse sweating. If the body is deficient in salt, this may produce a craving which should be satisfied if this is likely. Do not put extra salt on your meal. I often see people sprinkling salt profusely over a meal when they have not even tasted it. Reduce salt in cooking too. If you feel that salt brings out the taste in food and it is bland without it, try adding herbs or spices instead. Just as the palate adjusts to stopping sugar in tea or coffee, the palate adjusts to stopping salt. Television chefs frequently use a great deal of salt and their recipes often contain much saturated fat too. Regardless of whether a person has hypertension (high blood pressure) or not, reduction in salt is beneficial in lowering it a little more. This was shown in a large systematic review and meta-analysis.18Effect of dose and duration of reduction in dietary sodium on blood pressure levels: systematic review and meta-analysis of randomised trials Even people with normal blood pressure benefit from a further reduction.

Do not add salt at the table

When a person is diagnosed with hypertension, trying to reduce salt in the diet is often a first-line approach before medication. Also reduce alcohol intake if it is high. In the days before we had adequate drugs to treat hypertension, a severe, low-salt diet was used. The Kempner rice diet was developed by Dr Walter Kempner in 1934.19Rice Diet Founder Dr Walter Kempner It had some benefit but was unpalatable and not as effective or as acceptable as modern treatment.

The Dietary Approaches to Stop Hypertension, better known as the DASH diet and modifications to the DASH diet, coupled with reductions in sodium intake, is effective in lowering blood pressure and risk factors for heart disease.20The role of diet for prevention and management of hypertension.

The adverse effects of excessive salt consumption may not be limited to blood pressure. A paper which examined urinary tract infection in both humans and mice, found that a high salt diet had an adverse effect on hormones in the kidney which impaired the function of neutrophil white blood cells.21A High-Salt Diet Compromises Antibacterial Neutrophil Responses Through Hormonal Perturbation It concluded that a high salt diet impairs immunity.

Protein versus Carbs

I did not know whether to call this “protein versus carbs” or “fat versus carbs” as as even lean meat contains quite a lot of fat. However, as it is the protein content that is promoted more than the fat, I chose to call it “protein versus carbs” but remember that it will include a significant amount of fat.

There is a significant amount of protein on the right too

It is not just the self-appointed gurus who argue about carbohydrate versus fat. This is a matter of serious research and debate from proper scientific nutritionists.22Low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities A high carbohydrate diet will contain such foods as bread and potatoes and even vegetables will provide enough protein to meet daily needs. Vegetarians can have a perfectly adequate diet. However, a vegetarian diet is not necessarily a healthy diet as it can be high in salt and fat. A high fat or a high protein diet may be better called a fat and protein diet as it is typified by bacon and eggs which represent both. I think that much of the problem is with poorly informed people such as bloggers and personal trainers, who fail to differentiate between the various types of carbohydrate.

High carbohydrate foods

A high carbohydrate diet will give plenty of roughage and vitamins. It supplies a good source of glucose and this is the food of the brain. People on a high carbohydrate diet perform better on mental tests than when they are on a low carbohydrate diet. 23Macronutrients and mental performance It also provides a good source of glucose which is the basic food of muscles too and this gives better stamina and fitness.24Eating for performance: bringing science to the training table It does not seem to result in undesirably high levels of insulin. A high fat diet rather than a high carbohydrate diet seems more likely to lead to diabetes.25High-complex carbohydrate or lente carbohydrate foods? High insulin levels, as in type 2 diabetes, lead to the complications of high blood pressure, heart attacks and strokes.

NHS Choices addresses the issue of low carbohydrate diets and blames much on fad diets such as the Atkins diet that restricts carbohydrate but loads protein and hence fat too.26The truth about carbs. NHS Choices This diet has a very high drop-out rate. Users feel unwell, are constipated with such low fibre and have bad breath. There is ketosis which is a condition found in a diabetic crisis when fat is being metabolised instead of glucose because of a shortage of insulin. Personally, I think that it aids weight loss because the user feels too unwell to eat. Ketosis is very unpleasant and is potentially dangerous.

A systematic review and meta-analysis of low carbohydrate diets concluded that such diets were associated with a significantly increased risk in mortality from all causes.27Low-carbohydrate diets and all-cause mortality This is a very serious finding in view of how much such diets are promoted. Dr Atkins, the founder of the Atkins diet, died young and overweight of heart disease.

High protein foods

Protein is much more effective than carbohydrate in causing the feeling of satiety so that the person stops eating rather than continuing to take in calories.28Dietary protein – its role in satiety, energetics, weight loss and health A fat and protein diet has a worse effect on mental function and insulin resistance. The brain needs glucose. The effect of a protein and fat diet on blood cholesterol is not as bad as may be expected. The person on a high fat and protein diet has ketosis29High Protein, Low Carb Diets Explained and constipation as there is little fibre. Expert advice about red meat is that it should be limited, especially processed food such as bacon because of an increased risk of bowel cancer.30Red meat and the risk of bowel cancer The body needs glucose and if it cannot get it directly from the diet it will break down protein in muscle to release it.31Dietary protein and bone health For the person on a high protein diet to build muscle this paradoxical effect will be alarming. For us all, we do not want loss of protein and muscle.

In animals, carbohydrate is stored as glycogen, not starch. This is found in muscles and the liver

There is no good evidence to suggest that a diet that is low in carbohydrate is a healthy diet although sugars should be restricted. All types of food may be acceptable in moderation unless there is a problem such as allergy. Diabetics used to be advised to keep to a low carbohydrate diet which meant a high fat diet. They are at very high risk of coronary heart disease and this increases it. Nowadays they are advised to keep fats low and to eat carbohydrates but with a low glycaemic index. This is probably the sort of diet that we should all eat. Carbohydrates give glucose and this is the basic unit of energy in the body. We also need fat, protein, fibre and vitamins but the key to all is variety and moderation.

A population-based study with pooling of prospective studies, suggested that low carbohydrate diets were associated with increased overall mortality as well as links to specific causes such as cancer, heart disease and stroke.32Lower carbohydrate diets and all-cause and cause-specific mortality Once again, the very low carbohydrate diet comes out badly.

Identical twins Xand and Chris went head-to-head

A Horizon programme on BBC television in 2014 was an interesting trial although not scientifically robust. It followed two doctors who were identical twins and so had identical genes. One was on a high carbohydrate, low fat diet. The other was on a high fat and protein and low carbohydrate diet. The one on a high carbohydrate diet did much better on a test of mental agility and memory. He also did much better on a cycle race up Box Hill in Surrey. Both had no significant change in body weight or blood cholesterol. The one on a high fat and protein diet had a higher fasting blood glucose that was just outside the diabetic range. It would have been better to have had greater numbers and to randomise them to one of the diets. After a break of three or six months those on the high carbohydrate diet take to a high fat and protein diet and vice versa. That way they would have acted as their own controls. Nevertheless, the results were impressive.

A prospective cohort study with meta-analysis concluded that both high and low levels of carbohydrate intake were associated with increased mortality. The lowest risk was observed at an intake of 50 to 55% carbohydrate. Low carbohydrate diets, favouring animal-derived protein and fat sources, from sources such as lamb, beef, pork, and chicken, were associated with higher mortality, whereas those that favoured plant-derived protein and fat intake, from sources such as vegetables, nuts, peanut butter, and whole-grain breads, were associated with lower mortality, suggesting that the source of food notably modifies the association between carbohydrate intake and mortality.33Dietary carbohydrate intake and mortality

Provision of a high fat or high carbohydrate diet is not as simple as that. A high fat diet should limit the amount of saturated fat and contain plenty of unsaturated fats. This is to reduce the rise in blood cholesterol. A high carbohydrate diet may have a high or low glycaemic index. This is the rate at which glucose is released. A slow release seems to be good but fast sugars lead to a massive insulin response, and this is bad. Starches and slow carbohydrates release glucose but sucrose which is sugar that we get from sugar beet and sugar cane releases equal amounts of glucose and fructose. Fructose is taken to the liver and laid down as fat. This can lead to a fatty liver with serious consequences for health. High fructose corn syrup is thought to be a major contributor to obesity on the USA.

Chocolate is high in fat and sugar and we love it

A combination that we crave so much that it leads to a food addiction is a mixture of fat and sugar. The most appealing type seems to be about an equal mixture of fat and sugar. This is not found in nature but only in processed foods. Fast foods are typical of these foods with fat and sugar, especially if fatty foods such as burgers are washed down with sugary drinks.34Is fast food addictive? In addition the sugary drink may contain caffeine in levels that can add to the addiction.

A high protein diet is often recommended as being good for weight loss and helpful for those who are in physical training, especially if trying to build muscle. The average western diet probably contains rather more protein that we really need and increasing this further may have an adverse effect on kidney function, especially in those at risk of kidney disease such as the obese and diabetics. A study from the Netherlands found that in people who have had a myocardial infarction (heart attack), a high protein diet is associated with more rapid decline in renal (kidney) function. 35Dietary protein intake and kidney function decline after myocardial infarction It is easy to suggest that this risk applies only to those at height risk such as those with heart disease or diabetes, but a cohort study from South Korea suggested that a high protein diet impairs kidney function, even in the general population. 36High-protein diet with renal hyperfiltration is associated with rapid decline rate of renal function: a community-based prospective cohort study

A high protein and low carbohydrate diet is not as healthy as many would claim

An accompanying editorial notes that a high protein diet is currently promoted as the safe way in modern times, but even people with normal renal function may be at risk with diets that get 20 to 25% of their Calories from protein. They say, “We are being told that getting plenty of protein is the revival of our hunter–gatherer ancestral spirit and it will help maintain our lean muscle and reduce fat mass.” However, they add these two new studies, and other data suggest that it is time to unleash the taboo and make it loud and clear that a high-protein diet is not as safe as claimed. 37 High-protein diet is bad for kidney health: unleashing the taboo

The sensible answer again seems to be moderation in all things. Eat a mixed diet but carbohydrates with a low glycaemic index should predominate. They should probably be the main source of Calories. A breakfast such as bacon and eggs can sometimes be a good start to the day but restrict the total amount of red meat in a week and also the amount of saturated fat. Do not eat bacon every day. Too much red meat and processed meat such as bacon and burgers increase the risk of bowel cancer. Keep total fat and protein intake reasonable. Eat fresh food rather than processed food and take a variety of colours. It is not necessary to adhere to this all the time. Treats are allowed. Even diabetics can be naughty at times so long as it is not too often. Even the occasional MacDonald’s is unlikely to be fatal.


Perhaps after Christmas you realise that you have been eating and drinking too much and abusing your body. Perhaps the demands of everyday life have led you to eat fast or junk food. You consume a great deal of coffee during the day and you relax with too much alcohol in the evening. You feel sluggish and in poor health. It is time to rid your body of all the nasty toxins that you have been consuming and poisoning your body.

There are many unnecessary products for sale

There is no shortage of charlatans to offer you expensive diets, herbs, drinks or even enemas to rid your body of these toxins. Enemas are certainly a kinky way of doing it. High colonic lavage means an enema to reach up to the highest part of the large intestine to empty out its contents. The technique was popular with the late Princess Diana. Enemas are sometimes required in medical practice where there is severe constipation and even impaction. However, emptying the contents of the bowel clears the good bacteria from the bowel too. The flora of the gut is very important as has been discussed above.

Look first at what you take in each day. If you smoke, stop and never start again.

Caffeine is not the poison that some would pretend but, as has been noted in previous sections, the difference between a medicine and a poison is the dose. It is a useful stimulant that is found in coffee, to a lesser extent tea and in cola drinks. Some similar substances are present in chocolate. Caffeine helps to wake us up in the morning and to keep us going through the day. Old studies from the days before computer spreadsheets showed that clerks who add up figures find that it increases both speed and accuracy. However, an excess of caffeine can cause anxiety, tremor, reduced appetite and if taken too late in the day, insomnia. It can also cause irregularities of the heart in very high doses. Poor sleep can lead to poor concentration and weight gain.

Ignore the primeval slime. Cut out the bad things and the excesses and eat proper food

Think of cutting back rather than stopping completely, perhaps converting some cups of coffee to tea and using de-caffeinated drinks at times, especially in the evening. Some forms of coffee, such as espresso, are very high in caffeine and drinking too much caffeine in a day is bad. Colas and various “energy drinks” often contain caffeine, perhaps in quite large amounts. High levels of caffeine can be addictive. Cola may contain sugar, but sugar-free versions are also available. Sugar is bad for the teeth. Cola contains phosphoric acid. If you have not seen this done, leave an old dirty copper coin in a saucer of cola overnight. In the morning it will be shiny. Imagine what that does to the enamel of your teeth.

An American review expresses concern about adding increasing amounts of caffeine to drinks and other consumables, the promotion of these as performance enhancers and the targeting youth.38Caffeine addiction? Caffeine for youth? Time to act! A PubMed search for caffeine and youth will show many causes for concern with regard to very high caffeine intake in some adolescents and the mixing of caffeine and alcohol. A moderate intake of caffeine is fine. A very high intake is not.

Alcohol may be cut back to sensible levels or stopped and then restarted at moderate rather than binge levels. The potential positive and negative effects of alcohol has been examined above.

Take some exercise. Find something that you like so that you will persevere.

Have proper cooked food with fruit and vegetables and no added salt. If you are overweight, try to get back to a more suitable weight with a mixture of diet and exercise.

The verdict on de-tox is that if you have a functioning liver and two functioning kidneys, that is all you need to rid your body of toxins. You do not need anything else and you do not need to drink several litres of water a day.


Oxidative stress is when cells are damaged by oxidation. It has been a very productive field of cell biology since the 1990s and into the 21st century. There are many thousands of papers in peer-reviewed journals. Oxidative stress has been linked to atherosclerosis and with it risk of heart attacks and stroke. It has been linked to cancer and to hypertension (high blood pressure). It has been linked to the complications of diabetes and end stage kidney failure. It has been linked to Alzheimer’s disease and the aging process in general. It really does seem to be at the cutting edge of the understanding of the pathology of much disease.

Pollutants are a cause of oxidative stress

Oxidative stress is enhanced by smoking39Acute effects of cigarette smoke on inflammation and oxidative stress and by air pollution40Long term exposure to ambient air pollution and incidence of acute coronary events and it is reduced by regular exercise.41Effect of exercise on oxidative stress We know that smoking is associated with increased atherosclerosis and with many types of cancer along with more rapid progression of the complications of diabetes. It accelerates the aging process including in the skin. We also know that air pollution can precipitate disease and that regular exercise is good for health.

Oxidative stress and antioxidants are not as simple as is often suggested

There seems to be no doubt from in vitro experiments, meaning in glass in the laboratory, that oxidative stress is very important in disease and that antioxidants are beneficial. The body produces its own antioxidants but some it needs to take in, including vitamin C, vitamin E and β-carotene which it converts to vitamin A. If oxidative stress is the root of all evil, it makes sense to suppose that antioxidants will confer a vast number of benefits in terms of preventing or even treating cancer, heart disease, dementia, arthritis and even stalling the natural aging process. It must be the philosopher’s stone that the alchemists searched for over many centuries. However, when something seems to be too good to be true, it is usually not true.

There is no such thing as superfoods

Antioxidants seem to be wonderful in vitro. In experimental animals their value is rather more limited. In humans they simply do not live up to the promise.42Anti-oxidants- a protective role in cardiovascular disease? Having found that vast doses of vitamin C do not cure cancer or the common cold, perhaps we should not be surprised at the lack of ability to cure or prevent other diseases. Nevertheless, a healthy diet, rich in fresh fruit and vegetables is to be recommended.

Oxidative stress is also involved in HIV replication in vitro, but no one has attempted to do a proper trial of vitamin C for HIV in vivo. If you had HIV infection, would you want HAART (highly active anti-retroviral therapy) or high dose vitamin C?

A Cochrane review of antioxidant supplements in preventing gastrointestinal cancers concluded that, “We could not find convincing evidence that antioxidant supplements prevent gastrointestinal cancers. On the contrary, antioxidant supplements seem to increase overall mortality.”43Antioxidant supplements cannot be recommended for gastrointestinal cancer prevention This is not what the protagonists of antioxidants expected or wanted to hear.

The snake oil salesmen have jumped on the bandwagon of pseudoscience to sell the gullible all sorts of “super foods” that are supposed to cure diseases, prevent diseases, burn fat, aid the mind, enhance immunity and prevent the natural aging process. They are sometimes called “functional foods”. Supposed super foods include berries, especially blueberries, broccoli and various nuts. One of the “super foods” named by the Daily Mail is baked beans.44Daily Mail. Extract from Nutrition for Dummies They are often high in salt and sugar. However, when it comes to properly controlled trials to test such hypotheses, there is a distinct lack of evidence. An Internet search will show all sorts of supposed “super foods” that are alleged to do all sorts of wonderful things. The truth is:

  • The science behind oxidative stress and free radicals is quite complex and difficult.
  • It does seem to be important in terms of a vast array of diseases, at least in the laboratory but not in living animals or humans.
  • Evidence that antioxidants prevent or cure disease in humans is lacking.
  • There is no such thing as super foods.45Miracle food, myths and the media
  • Stick to a varied diet that is rich in fresh fruit and vegetables but not to excess.
  • Do not smoke.
  • Take regular exercise.

An extensive review by the respected Cochrane Library assessed trials comparing the effects of a range of vitamins and also selenium on death rates.46Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases It was one of the biggest reviews of the effects of vitamin supplements on mortality to date, assessing the results of 67 trials and data on more than 232,000 people. Despite the seemingly plausible mechanism, the results do not provide the reassurance that many taking antioxidant vitamins would wish to hear.

The study found no reduction in mortality in people who took antioxidant supplements, either in healthy people or in those with diseases. Separately, the results on vitamins A and E and beta-carotene suggest that they may even increase the risk of death although these results only just reached statistical significance. Therefore, the reviewers call for further trials to be “closely monitored” for potential harmful effects. A review of the commonly used antioxidants gives no backing to the claim that they help to prevent cancer.47Clinical trials of antioxidants as cancer prevention agents This review was in “Free radical biology and medicine” and so all concerned were presumably well versed in the concepts of free radicals. A trial that was supposed to show the benefit of vitamin E and selenium in prevention of prostate cancer showed that it increased the risk.48Baseline Selenium Status and Effects of Selenium and Vitamin E Supplementation on Prostate Cancer Risk

The findings are leading to a rethink about free radicals, with the Cochrane researchers saying that by eliminating free radicals from the body we may be interfering with essential defensive mechanisms. Oxidation is a part of numerous chemical reactions in the body and there is some scientific debate over whether taking huge doses of antioxidants might upset the natural balance of these reactions. Cell death, called apoptosis, is important in the prevention of cancer.

Apoptosis is important to kill off cells that are going bad. High dose antioxidants may impair this

The body kills off rogue cells before or when they turn malignant. If this is impaired by excessive levels of antioxidants, it may account for the increased risk of cancer. As with all research, there are important points to note about the scope of this review. It looked only at mortality, not effects on health, and most of the trials in the review used high-dose supplements.

Therefore, the findings may not apply to low-dose vitamins or to the antioxidants found in food as part of a normal diet. It does show that the antioxidant issue is complex and, given the results of this research, it would seem sensible for most of us to rely on a balanced diet for our intake of antioxidants. It may well transpire that a moderate intake of vitamins and antioxidants is good, but an excessive amount is bad.

There is much hype and little true science about antioxidants

It seems that inflammation is important in the processes that lead to coronary heart disease, strokes, aging, dementia and much more. What we eat can have an effect on this background inflammation. An enormous prospective study of 74,578 women and 43,911 men who were healthy at baseline was followed for 32 years to give 5,291,518 person-years of follow-up. Diet was assessed by food frequency questionnaires every 4 years. The inflammatory potential of diet was evaluated using a food-based empirical dietary inflammatory pattern (EDIP) which the authors had developed. They concluded that diets with a higher proinflammatory potential were associated with more disease of the heart and circulation. Reducing the inflammatory potential of the diet may reduce this risk.49Dietary Inflammatory Potential and Risk of Cardiovascular Disease Among Men and Women in the U.S.

A higher consumption of green leafy vegetables such as kale and spinach, as well as dark yellow vegetables, including pumpkin, yellow peppers and carrots, and also whole grains, fruits, tea, coffee and wine reduced long-term cardiovascular risk (diseases of the heart and circulation) compared with those with higher intakes of red meat, processed meat, organ meat, refined carbohydrates, and sweetened drinks. Extra-virgin olive oil, fatty fish, and tomatoes also have anti-inflammatory activity.50Proinflammatory Dietary Pattern Linked to Higher CV Risk


Nutrition is not just about food, but it includes drink and hydration. In the summer of 2012, just before the London Olympics, there were a series of articles in the BMJ criticising many products that were sold to athletes because they claimed to have scientific validity that was absent. The one that was savaged the most was sports drinks. The articles about sports drinks are no longer available online, so I have removed the reference. Most of the rest of this section is derived from this reference. The only article that is freely available without charge is “The evidence underpinning sports performance products: a systematic assessment.”51The evidence underpinning sports performance products

There is a wide array of sports supplements of dubious value

The team at the Centre for Evidence Based Medicine at Oxford University assessed the evidence behind 431 performance enhancing claims in advertisements for 104 different sports products including sports drinks, protein shakes and trainers. Only three (2.7%) of the studies were judged to be of high quality and at low risk of bias. They say this absence of high-quality evidence is “worrying” and call for better research in this area to help inform decisions.

Sports drinks are a triumph of marketing over evidence

Dehydration does have an adverse effect on performance, but the new “disease” of dehydration has been taken to ridiculous extremes. Joggers go out on a Sunday morning clutching a water bottle in their hand. This will make very little difference to their performance when they are probably not going very far or very fast. This is not sports science. This is an affectation, but it does sell plastic water bottles. Many schools in the UK now encourage children to stop every 15 to 20 minutes during exercise to drink. The BMJ said that this is based on supposedly expert advice, but it was written by people with financial links to the sports drinks industry and it does not stand up to scrutiny. In fact, having to stop every 15 to 20 minutes for a drink is quite ridiculous.

How safe is your water bottle?

Even the plastic water bottle may not be as innocuous as we think unless it is BPA free. Bisphenol A (BPA) was first synthesized in 1891. Its oestrogenic properties were discovered in 1930, and shortly after that it was found to be useful in the production of epoxy resins. Since the 1950s, BPA has been used as in the manufacturing of polycarbonate plastic, polystyrene resins, and dental sealants. Roughly 3 million tons of BPA are produced each year and the oestrogenic compound leaches into nearby water and food supplies. I do not intend to delve further, but a review called “The role of Bisphenol A in shaping the brain, epigenome and behaviour” makes sobering reading.52The role of Bisphenol A in shaping the brain, epigenome and behavior I now take a BPA-free water bottle to the gym but I wonder how much BPA we take in food and drink that comes in plastic containers or wrapping.

Much supposedly expert advice comes from people who are employed by the manufacturers of sports drinks. The value of sports drinks in the UK alone is thought to be around £260 million a year. The science is often seriously flawed but not the marketing. This is the fastest growing area of the soft drinks industry.

There are plenty of water stations on modern marathon courses. I hope the rubbish gets cleared

Endurance events such as the marathon have ample drinking stations where those who feel thirsty may drink. If we are truly dehydrated, we feel thirsty and no athlete with access to water will become dehydrated.53Role of hydration in health and exercise The articles in the BMJ were very clear about this. Over-hydration in endurance events is a much more common problem than under-hydration. If too much water is drunk this reduces the blood sodium level and this is far more dangerous. Symptoms include changes in mental function from mild withdrawal to confusion and possibly seizures and coma. Furthermore, athletes with this condition may have persistent thirst and so continue to drink, thereby aggravating the condition. After a marathon many more people need treatment for over-hydration than under-hydration. This is especially true of those who are not very good runners as they spend more hours on the course expending fewer calories per hour and so sweating less.

Nowadays, most people who start a marathon finish it

There have been 16 recorded deaths and 1,600 people taken critically ill during competitive marathon running due to a drop in their blood sodium. This means over-hydration. There is no evidence that anyone doing a modern marathon has ever died of dehydration. Nevertheless, it is dehydration that gets the attention because this is where the market lies. In the old days it was different, when runners did not have water stations, but they may be given brandy and raw eggs on the way round, as well as strychnine injections. Back then, only about half of starters finished. Nowadays, events such as the London Marathon may have in excess of 50,000 starters and more than 95% finish.

It has been declared that athletes should drink as much as is tolerable. They advise that thirst is not a reliable guide to dehydration. The authors in the BMJ strongly disagree. No one mentions the serious problem of over-hydration. The companies that produce the products have managed to get their appointees and employees on to expert committees so that so that their message has come across as the official stance. Sports bodies receive generous funding from the industry, and they repay.

There are several types of fault in the evidence. Sometimes the scientific evidence is nothing like as strong as is implied. On other occasions it does apply to elite athletes in serious training but that does not mean that it can be extrapolated to the rest of us mere mortals who are trying to keep fit and keep our weight down. One of the articles in the BMJ states, “Over the past 40 years humans have been misled—mainly by the marketing departments of companies selling sports drinks—to believe that they need to drink to stay ahead of thirst to be optimally hydrated. In fact, relatively small increases in total body water can be fatal.”

If you need to drink, your brain makes you thirsty

Fluid is not absorbed directly from the stomach to any significant extent and for water or other nutrients to be absorbed, they must empty into the small intestine. Plain water will empty quite quickly. Proteins and more especially fat will slow the rate of stomach emptying considerably. This is the rationale for having something fatty to eat before embarking on a night of drinking alcohol. It does not coat the stomach to prevent alcohol from being absorbed directly into the circulation. No significant absorption occurs directly from the stomach. A very small amount of dissolved salt and sugar may cause the fluid to empty faster from the stomach than plain water. This is called an isotonic solution as the concentration and osmotic pressure is the same as in the blood. Hence, some sports drinks are advertised as being isotonic. However, whether this is practically important is rather dubious.

Sometimes advertisements suggest that their product will rehydrate faster after exercise. This may be true, but it does not matter? There is no great urgency after the exercise is over. More concentrated drinks would empty from the stomach more slowly and are not to be recommended. This applies particularly to drinks that are high in sugar. The value of the Calories in sports drinks or other drinks in an endurance event such as the marathon is rather dubious. Eating plenty of carbohydrate the night before is much more important. The value of glucose during exercise is an example of bad and biased science as some of the research was based on people who had been starved before exertion. This is not a normal situation in sport.

Sugar drinks are not a healthy option

For a great many of us who are not elite athletes or serious club athletes, a major benefit from exercise is to lose weight or to try to prevent us from getting fat. Therefore, if we are out exercising to lose weight and taking in Calories, it will undo at least some of the benefit which we are hoping to obtain.

There is often an implication on the websites that taking sugar during exercise prevents the blood glucose level from falling too far. This is not said overtly but it is certainly implied. This is nonsense. Diabetics try hard to prevent their blood glucose from getting too high as there is strong evidence that this is linked to complications including coronary heart disease and stroke. If a diabetic takes too much insulin and blood glucose falls too far, there will be confusion, incoordination, aggression, slurred speech and if it falls far enough, there may be convulsions and even death. However, those of us who are not diabetic do not have that risk. The body has a system involving insulin and glucagon which keeps blood glucose within a normal range. Non-diabetics who exercise, even to exhaustion, do not have blood glucose below a normal fasting level. High blood sugar does not confer any advantage such as getting glucose into the muscles more readily. Glucose is actively absorbed into muscles with the help of insulin and exercise improves the sensitivity to insulin.

The marketing of such product as “sports drinks” or “energy drinks” can even give the impression that the person is looking after his body and improving his fitness without breaking into a sweat. Lucozade Lite™ is advertised as “fitness hydration”. It does help hydration as it contains water. So does the stuff from the tap. Fitness you must achieve yourself. Simply drinking the product will not make you fit.

A team from University College London reported on findings from a dental clinic to treat sportsmen and women at the 2012 Olympics.54Oral health and impact on performance of athletes participating in the London 2012 Olympic Games They found a considerable amount of tooth and gum disease in people who may be expected to be in excellent general health. Although it was not possible to make a definitive statement about the cause of this poor dental health, a likely candidate is taking a lot of sugary drinks. It seems reasonable to suggest that sports drinks are rotting their teeth and the athletes would do better with plain water.

Sugar rots teeth

There was a similar report, also from University College London after the 2016 Olympics. Athletes often consume “energy drinks” containing sugar. Despite being more meticulous than most in brushing their teeth, they tend to have more dental decay than the general population.55Athletes have poor teeth despite brushing They found that 94% of athletes brushed their teeth twice a day compared with 75% of the general public and 44% flossed regularly compared with 21% of the public. They also found that 87% of athletes used sports drinks, 59% used energy bars and 70% used energy gels. It has been a dictum for many years. Sugar rots teeth.

Conducting a large clinical trial is not easy and not cheap but it is the only way to test these products. Hence researchers are eager to take finance from people who stand to profit by a positive result. This can be a problem in drug trials and nowadays medical journals like to know and to publish the fact if the research or any of the researchers was funded by a body with a vested interest. There is pressure from the funders to present results in the most positive light. There is pressure not to publish negative findings. He who pays the piper calls the tune. That is not to say that all research funded by those with a vested interest is bad or fraudulent. However, it should be viewed with a degree of circumspection. It is unacceptable when expert guidance is written by people who are employed or funded by the sports drinks industry. The pharmaceutical industry often sponsors research into drugs, but they do not normally get to write the expert advice.

A well conducted scientific trial should involve a fairly large number of participants. The requirements for Randomised Controlled Trials have been discussed. Ideally the drinks should be disguised so that neither group knows which they are receiving. This is obviously difficult with water versus sports drink as they taste different, but one may contain sugar and the other an artificial sweetener. If it is a single event such as a marathon race, it is important that the people in the test group and the control groups are similar. If it is a time trial it may be possible to run it twice and on each occasion the person has either the test or the control drink. Hence, they act as their own control.

Plastic water bottles litter the London Marathon

The trials that have been used to assess sports drinks have often used too few people to have a good chance of really showing significance. If they are a narrow group, such as highly trained cyclists, it is not necessary to have as many as if they are a diverse group such as middle-aged men and women who are trying to keep fit. In a review of 106 studies of marathon runners, there was one study with 257 runners, and this was the only with more than 100 subjects. For small group studies, 100 subjects is generally regarded as the smallest acceptable size. The next largest study was 54 subjects and the median size was nine. Median means that half the studies had nine or more subjects and half had nine or fewer. In other words, most of the 106 studies were not just small but tiny and unreliable.

It is important to measure something that is both relevant and important. Many studies used time to exhaustion or other outcomes that are not directly relevant to performance in real life events. Biological outcomes do not necessarily correlate with improved performance. Reduction in use of muscle glycogen, for example, did not correlate with improved athletic performance. Glycogen is how glucose is stored in muscle. Physiological outcomes such as maximal oxygen consumption have also been shown to be poor predictors of performance, even among elite athletes.

Another problem is that results have been based on highly trained athletes and then assumed to be just as applicable to the ordinary population. This is not valid.

Selective publication of small trials has been discussed before. It is as important to know what does not work as what does. Many of the people on the editorial board of sports medicine journals are in the pay of the sports drinks industry and so they may be reluctant to publish papers that are not in the interest of their paymasters and rather too eager to publish those that are. The industry has funded hundreds of such trials. It is easy to pick and choose what to publish.

In summary:

  • Drink according to thirst and do not try to keep ahead of dehydration.
  • Over-hydration in sport is much more of a danger than dehydration.
  • Sugar in drinks is unlikely to be beneficial to any but the best athletes competing in arduous events. Most of us want to burn off as many calories as possible. Sugar may also cause tooth decay.
  • Do not be impressed by claims of scientific evidence for most sports products as the level of evidence of generally very poor and any research has probably been funded by the industry.

Sport is good for us and the London Olympics of 2012 had an intended legacy of improved health. It is generally accepted that the biggest contributors to the epidemic of obesity are fast foods and sugary drinks. The biggest sponsors of the Olympics are Coca Cola and MacDonald’s. The athletics stadium for the London Olympics boasted the biggest MacDonald’s in the world. Money talks. They like to be associated with healthy pastimes as it gives a “halo effect”. It was the same with tobacco advertising in sport.

Bottled water is about 500 times the price of water from the tap

I never cease to be amazed when I see rows and rows of bottled water in supermarkets. This country has safe, drinkable water coming from our taps. I see people with stacks of bottled water in their trolleys. Hugh Fearnley-Whittingstall, among others on television, have demonstrated that most people are unable to taste the difference between bottled and tap water. Bottled water is no more healthy. Indeed, it may contain BPA, as mentioned above. It is also about 500 times the price of metered tap water. To draw a comparison, you may be happy to pay £4 for a pint of draught beer, but would you pay £2,000 for a pint of bottled beer? This is a tribute to marketing over substance.

E Numbers

Additives may be put in food for many reasons. Salt and smoking have been used to preserve food for many centuries. Whilst some people may disparage the use of preservatives, eating food that is rotten is far more dangerous to health. In this country we throw out vast amounts of food, often for spurious reasons such as failing to understand the difference between sell by or best before dates and use by dates or because excessive amounts have been bought as part of a deal such as three for the price of two. Throwing out excess food is rarely good value for money. Antioxidants stop food becoming rancid or changing colour by impairing the oxidation of fats. Preservatives keep food safer for longer. Some additives are to enhance the flavour of food. Some add colour. Emulsifiers, stabilisers, gelling agents and thickeners help to mix or thicken ingredients. Sweeteners may be intense and many times sweeter than sugar whereas bulk sweeteners have a similar sweetness to sugar. Legislation from the EU requires most additives used in foods to be labelled clearly in the list of ingredients, with their function, followed by either their name or E number.

According to the Foods Standards Agency, an E number is an additive that it has passed safety tests and has been approved for use here and in the rest of the EU.56Additives or E numbers. Foods Standards Agency This is in contrast to The Daily Mail (of course!) which states, “Some are known to be carcinogenic or toxic, while others may cause hyperactivity in children, and contribute to allergies, asthma and migraines.”57Just how dangerous are those E numbers?

There is nothing sinister about E numbers

There is no shortage of websites trying to tell readers that E numbers are poisoning us. Many people see E numbers as synonymous with unhealthy food. There are around 319 E numbers and the authorities are constantly reviewing them. This applies to applications for new products but also to new evidence about existing E numbers.

To suggest that every E number is bad and should be avoided is ridiculous when they include such substances as riboflavin (E101) which is one of the B vitamins and ascorbic acid (E300) which is vitamin C. Calcium carbonate (E170) is chalk and citric acid (E260) is found in citrus fruits and is part of the metabolic pathway as glucose is broken down to carbon dioxide and water. E948 is oxygen and E290 is carbon dioxide. However, not all E numbers are quite as innocuous as that.

Colours can be a problem for young children

An area of concern is colourings. There is evidence that some bright colours can cause hyperactivity in small children.58Artificial food colourings and benzoate preservative in preschool children This was a double-blind placebo controlled trial. Parents often see this after a party, and they attribute the child’s behaviour to being too excited, but the child may have been consuming large amounts of brightly coloured sweets and cakes. This effect appears to be limited to young children and whilst diet may have some effect on attention deficit hyperactivity disorder (ADHD), colourings are not so important.59The diet factor in attention-deficit/hyperactivity disorder

A PubMed search for food additives causing cancer did not yield anything of note. A search for tartrazine which seems to be one of the most reviled, found no evidence.

We have to have faith in those who administer the Foods Standards Agency in this country and their European counterpart that if there was really any good evidence of toxicity in any specific product, they would take action. Ignore the conspiracy theorists and pseudoscientists and trust the real scientists. Trying to eat an E number free diet is to be delusional. Most additives are only permitted to be used in certain foods and are subject to specific limits. However, we may decide that we would prefer to avoid foods that contain artificial colouring as unlike preservatives, they do not offer obvious benefit. Keeping the more luminescent colours away from small children may be wise, especially if they seem to have an adverse effect. Otherwise, enjoy the enhanced flavour and longer fridge life that they offer.

Organic Food

Mad Cow Disease was an absurd and inaccurate name

Back in the 1980s and 1990s, the British farming industry was going through a very bad patch. Eggs were often contaminated with Salmonella, although the minister, Edwina Curry, made some remarks that were neither accurate not helpful. Then there was the outbreak of bovine spongiform encephalopathy (BSE) or “mad cow disease”. Cows did not suffer from mental illness but had a nasty neurodegenerative disease. Both were apparently associated with bad farming practices in a small section, but the entire industry suffered. There was also foot and mouth disease, which is devastating to animals, but it does not affect humans. It was this lack of confidence in farming that led to the business opportunity called organic farming or organic food. Organic chemistry is the chemistry of carbon chain molecules and it includes all food. There is no such thing as inorganic food. It is the image that matters in marketing, not the substance. The image is that of a gentile and pure form of farming in which there are no fertilisers, no pesticides, food is entirely wholesome and nutritious and even the cows have a smile on their faces. The evidence, however, is that organic foods are no more nutritious than any others.60Are organic foods safer or healthier than conventional alternatives? What is certain is that it is invariably more expensive. This is inevitable as productivity is also considerably lower.

The idea that organic farmers do not use fertilisers is a myth. They are permitted to use a great many types of different fertilisers61The Soil Association. Fertilisers but the image is that at least they are not chemicals. The whole world is made of chemicals. They get their phosphates, nitrates and other chemicals but in a different form. It may include faecal matter and bacterial contamination of organic food can be a serious problem if the suppliers are not meticulous. An outbreak of E coli infection from Germany in 2011 was linked to beansprouts from organic farming.62E.coli outbreak poses questions for organic farming In 2012 a large outbreak of E coli infection in the USA was linked to organic spinach.

They are always more expensive

Similarly, organic does not mean pesticide-free and there are a great many pesticides that are permitted.63Organic Food FAQ. Health and Safety Executive. The WebMD site listed six myths about organic food.646 myths about organic food They were:

  • Organic food is always better for the environment
  • It is more nutritious
  • It tastes better
  • You do not have to be as careful about washing it
  • You are supporting small farms and eco-companies
  • It is better for you.

The website expands on all six fallacies.

Even scientists have been lulled by the hype about the safety of organic farming. When synthetic chemicals such as pesticides are tested for carcinogenesis (ability to cause cancer), around half test positive. Testing of organic pesticides has been slow to take off but about half of them are also positive for carcinogenesis.65The Organic Label Organic pesticides tend to be less effective than conventional ones and so must be applied more often. Hence it may be necessary to make seven applications of rotenone and pyrethrin, organic pesticides compared with two applications of the standard imidan. It seems unlikely that seven applications of rotenone and pyrethrin are really better for the environment than two applications of imidan, especially when rotenone is extremely toxic to fish and other aquatic life. We do not know how long organic pesticides persist in the environment, or the full extent of their effects.

Organic is more about marketing than substance

Organic produce is about image, not substance. “Natural” is not synonymous with safe. Organic farmers may claim that they do not use “chemical pesticides” but they do use pesticides and like everything on earth they are chemicals. They like to suggest that conventional pesticides are carcinogenic (produce cancer) but they lack evidence. A paper based on the million-women study used to assess HRT asked if eating organic food reduced the risk of some cancers. They failed to find any association except perhaps a slight reduction in the incidence of non-Hodgkin’s lymphoma.66Organic food consumption and the incidence of cancer However, a French study using data from the NutriNet-Santé Prospective Cohort Study found that the consumption of organic food was associated with a reduced risk of cancer.67Association of Frequency of Organic Food Consumption With Cancer Risk However, the methodology has been criticised. Whether or not eating organic food offers any advantage to health is still unclear.68Effects of organic food consumption on human health; the jury is still out! What is undeniable is that it is associated with poorer productivity and so it is more expensive.

If the whole world went “organic” there would be mass starvation.

Recombinant DNA technology (Genetically-Modified Food)

Frankenstein food

Genetically modified (GM) crops have been hysterically called “Frankenstein foods” and Europe has maintained a constant irrational opposition to them. All new foods have to be rigorously tested before going on the market regardless of their origin. The ignorance of activists can be amazing as in the statement, “I don’t want to eat genes.” Genes are DNA. Every cell with a nucleus, whether animal or plant, contains DNA. Even red blood cells and platelets that do not have a nucleus still have mitochondrial DNA. If we eat chicken DNA, we do not grow feathers. Eating fish does not make us better swimmers. The case against GM foods, or to be more correct recombinant DNA technology, always seems to have been that there is much that is unknown about the dangers. GM crops have been extensively used throughout North and South America as well as much of the world outside Europe for many years. There have never been any problems with them as they need to be as fully investigated before introduction as any other type of crop.69GM crops don’t kill kids. Opposing them does Whilst America and much of the world benefits from this technology, Europe remains in the dark ages with its medieval attitude.

This sort of picture of injecting food is common in anti-GMO propaganda. It is also misleading and inaccurate

Professor Anne Glover, the chief scientific adviser to the European Commission, was the target of Greenpeace, GM Watch and seven other groups who wanted her removed for her outspoken views about opponents of recombinant DNA technology. They accused her of presenting one-sided, partial opinions in the debate. They have about as much idea of a balanced debate as Josef Stalin. She received support from Sir Paul Nurse, President of the Royal Society and Jonathan Jones, from the Sainsbury Laboratory. The Times also noted that GM crops are already grown by more than 17 million farmers in 28 countries on an area about seven times the size of Britain. The only GM crop to be commercially grown in Europe is pest-resistant maize that is cultivated in Spain. The pest does not occur in Britain.70Opponents of GM crops are a bunch of lunatics, say scientists

By November 2014 the fanatics had their way and Anne Glover was informed that her post had “ceased to exist” and that she would leave the EU Commission in January 2015.71Chief scientist is forced out after green campaign Professor Colin Blakemore said: “It’s a sad day for science, policy, politics and the public in Europe.” As The Times noted, “In the EU, a ragbag of pressure groups matter more than the experts.”72Juncker has given in to the lobbyists from Greenpeace Perhaps in the future we shall have more control over our destiny, but we shall still want to export to the EU.

A GM product called Golden Rice has been developed which contains beta carotene and so prevents vitamin A deficiency. However, Greenpeace has successfully prevented its release to developing countries that need it. Greenpeace can claim responsibility for the thousands of African children who go blind every year from vitamin A deficiency because of their rigid and unquestioning dogmatism.73Greenpeace accused over child deaths

Since 2012, a new and much more precise technique called gene editing has been available. It allows changes to DNA to be highly specific and accurate. A powerful tool is an enzyme called CRISPR-Cas9. It allows precise removal and insertion of DNA into the desired locations. It is far more accurate than previous techniques. I shall not go into any detail but a brief review from Britannica is found at 74Gene Editing. You may wish to find more resources on the Internet, but be sure to sort the science from the fiction. This technique can be more applicable to correcting genetic abnormalities in humans than older methods and so ethics need more urgent consideration. Again, this is not the time to go deeper.

There are two main types of vaccine against COVID-19. One uses m-RNA and the other a genetically modified virus. If we are happy with GM vaccines, why not GM food too?


In the world of advertising, something that is low in Calories is “slimming” whilst something that is high in Calories “gives you energy”. This means “contains lots of Calories” and it would be more accurate to say “makes you fat”. It does not make you want to get out of the chair and start to exercise.

Marketing is about giving the impression that a food or drink is health-giving regardless of the truth. A classic example is Sunny Delight that was later rebranded as Sunny D.75The rise and fall of Sunny Delight The image was of an orange drink bursting with vitamins and health-giving properties. In fact, it contained less than 2% each of Orange, Tangerine, Apple, Lime and Grapefruit juices. It contained high fructose corn syrup that has been associated with obesity and the orange colour was given by an abundance of β-carotene. Some children drank so much β-carotene that they turned orange.

Marketing may be misleading

Oats is a good source of nutrition with a low GI carbohydrate and fibre and a product such as Oats-so-simple with added fruit may seem better still. However, to take this product with apple and cherry as an example, a 58 grams pot contains 40 grams of carbohydrate of which 16 grams is sugars.76My net diary A product that is 27% sugar does not sound very healthy. However, a search for nutritional contents of Oats-so-simple produced a wide variety of information, even from Quaker’s own websites. I think that they change the formula from time to time. Oats has carbohydrates, some as sugar. Fruit has sugar. Just watch out for added sugar and avoid it.

Innocent Smoothies “100% pure fruit” also sound good. There are a number of other brands of smoothies, all of which contain rather a lot of sugar.77Which? Smoothies The consumer magazine Which? points out that some smoothies contain twice as much sugar as Coca Cola.78Is your fruit smoothie as healthy as you think?

Sponsorship of athletic events gives a “halo effect”, and no sporting event is more prestigious than the Olympic Games. The two biggest sponsors of the games are Coca Cola and McDonalds. The tobacco industry sponsored sport until it was stopped. Now it is the turn of fast-food and sugary drinks. The gambling industry is also keen to promote sport.

The marketing of fast food is often aimed at children

The source of funding for conferences or research is not always obvious. A series of journalism conferences on obesity received covert funding from Coca-Cola.79Coca-Cola’s secret influence on medical and science journalists The full reference is unavailable without payment, but a significant amount is. Industry money was used to covertly influence journalists with the message that exercise is a bigger problem than sugar consumption in the obesity epidemic. Documents obtained under freedom of information laws detail how Coca-Cola funded journalism conferences at a US university (I believe it was the University of Colorado) to create favourable press coverage of sugar sweetened drinks. When challenged about funding of the series of conferences, the academics involved were not forthcoming about industry involvement.

For drinks manufacturers such as Coca-Cola the idea that consuming their products is fine if you exercise is reinforced with expensive advertising campaigns associated with sport. They wish to cultivate the message that, even for soda drinkers, obesity is more a consequence of inactivity than it is of regularly drinking liquid sugar. Critics say that the six-figure bill for funding these journalism conferences was more than repaid in favourable press coverage. Documented evidence of the industry’s covert influence on the media is rare but it was found here.

They want the “halo effect” of association with sport

A network analysis of Coca-Cola’s research funding from 2008–2016 concluded “The Coca-Cola Company appears to have failed to declare a comprehensive list of its research activities. Further, several funded authors appear to have failed to declare receipt of funding. Most of Coca-Cola’s research support is directed towards physical activity and disregards the role of diet in obesity. Despite initiatives for greater transparency of research funding, the full scale of Coca-Cola’s involvement is still not known.”80Coca-Cola – a model of transparency in research partnerships?

This agenda, blaming inactivity rather than sugar consumption, is not limited to the western world. Coca Cola has also exerted its influence in China.81Soda industry influence on obesity science and policy in China There is an obvious parallel with the tobacco industry.

If we look at supplements, diets, advice, energy drinks and supposedly healthy foods, the conclusion must be that it is all about marketing to sell a product. It is not about science. Claims vary from unfounded to fraudulent. This chapter has barely scraped the surface of the issue but hopefully it will leave the reader in a better position to see through the hype and false promises. When you go shopping it can be very difficult to know what you are really buying. The simple traffic lights scheme has been opposed by the food industry. Remember again, if the claims seem too good to be true, they are almost certainly not true.

Further Resources


  1. Tong TYN, Appleby PN, Bradbury KE, Perez-Cornago A, Travis RC, Clarke R, Key TJ Risks of ischaemic heart disease and stroke in meat eaters, fish eaters, and vegetarians over 18 years of follow-up: results from the prospective EPIC-Oxford study. BMJ. 2019 Sep 4;366:l4897 [full text]
  2. Tong TYN, Appleby PN, Armstrong MEG, Fensom GK, Knuppel A, Papier K, et al. Vegetarian and vegan diets and risks of total and site-specific fractures: results from the prospective EPIC-Oxford study. BMC Med. 2020; 18: 353
  3. Healthy? Just because it’s vegan, doesn’t mean it’s good for you. The Times 10 November 2018
  4. Croall ID, Aziz I, Trott N, Tosi P, Hoggard N, Sanders DS Gluten Does Not Induce Gastrointestinal Symptoms in Healthy Volunteers: A Double-Blind Randomized Placebo Trial. Gastroenterology. 2019 Sep;157(3):881-883 [full text]
  5. Hansen LBS, Roager HM, Søndertoft NB, Gøbel RJ, Kristensen M, Vallès-Colomer M et al. A low-gluten diet induces changes in the intestinal microbiome of healthy Danish adults. Nat Commun. 2018 Nov 13;9(1):4630 [full text]
  6. Lebwohl B, Cao Y, Zong G, Hu FB, Green PHR, Neugut AI et al. Long term gluten consumption in adults without celiac disease and risk of coronary heart disease: prospective cohort study BMJ. 2017 May 2;357:j1892. [full text]
  7. Raehsler SL, Choung RS, Marietta EV, Murray JA. Accumulation of Heavy Metals in People on a Gluten-Free Diet. Clin Gastroenterol Hepatol. 2018 Feb;16(2):244-251
  8. Adan RAH, van der Beek EM, Buitelaar JK Cryan JF, Hebebrand J, Higgs S et al. Nutritional psychiatry: Towards improving mental health by what you eat. Eur Neuropsychopharmacol. 2019 Dec;29(12):1321-1332. [full text]
  9. Jacka FN, Kremer PJ, Berk M, de Silva-Sanigorski AM, Moodie M, Leslie ER, et al. (2011) A Prospective Study of Diet Quality and Mental Health in Adolescents. PLoS ONE 6(9): e24805
  10. Obesity and depression ‘hand-in-hand’ in children BBC 29th April 2019
  11. Simkin DR. Microbiome and Mental Health, Specifically as It Relates to Adolescents. Curr Psychiatry Rep. 2019 Sep 2;21(9):93
  12. Momen NC, Plana-Ripoll O, Agerbo E, Benros ME, Børglum AD, Christensen MK, Dalsgaard S, et al. Association between Mental Disorders and Subsequent Medical Conditions. N Engl J Med. 2020 Apr 30;382(18):1721-1731. doi: 10.1056/NEJMoa1915784.
  13. DeStefano F, Anda RF, Kahn HS, Williamson DF, Russell CM. Dental disease and risk of coronary heart disease and mortality. BMJ 1993 Mar 13;306(6879):688-91. doi: 10.1136/bmj.306.6879.688. [full text]
  14. Orzechowski A , Rostagno AA , Pucci S , Chiocchia G. Cytokines and Disease Mediators Inflamm 2014;2014:209041. doi: 10.1155/2014/209041. Epub 2014 Sep 14. [full text]
  15. Dantzer R, O’Connor JC, Freund GG, Johnson RW, Kelley KW. From Inflammation to Sickness and Depression: When the Immune System Subjugates the Brain. Nat Rev Neurosci. 2008 Jan;9(1):46-56. doi: 10.1038/nrn2297 [full text]
  16. Worry, Anxiety Tied to Increased Inflammation. Medscape 7 April 2020.
  17. He FJ, Li J, MacGregor GA. Effect of longer-term modest salt reduction on blood pressure. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD004937. DOI: 10.1002/14651858.CD004937.pub2
  18. Huang L, Trieu K, Yoshimura S, Neal B, Woodward M, Campbell NRC, et al. Effect of dose and duration of reduction in dietary sodium on blood pressure levels: systematic review and meta-analysis of randomised trials. BMJ 2020;368:m315 [full text]
  19. Rice Diet Founder Dr. Walter Kempner. The Way to Eat.
  20. Ozemek C, Laddu DR, Arena R, Lavie CJ. The role of diet for prevention and management of hypertension. Curr Opin Cardiol. 2018 Jul;33(4):388-393.
  21. Jobin K, Stumpf NR, Schwab S , Eichler M , Neubert P , Rauh M et al. doi: 10.1126/scitranslmed.aay3850. A High-Salt Diet Compromises Antibacterial Neutrophil Responses Through Hormonal Perturbation Sci Transl Med. 2020 Mar 25;12(536):eaay3850.
  22. Hession M, Rolland C, Kulkarni U, Wise A, Broom J. Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities. Obes Rev. 2009 Jan;10(1):36-50
  23. Dye L, Lluch A, Blundell JE. Macronutrients and mental performance. Nutrition. 2000 Oct;16(10):1021-34
  24. Bonci LJ. Eating for performance: bringing science to the training table. Clin Sports Med. 2011 Jul;30(3):661-70
  25. Jenkins DJ, Kendall CW, Augustin LS, Vuksan V. High-complex carbohydrate or lente carbohydrate foods? Am J Med. 2002 Dec 30;113 Suppl 9B:30S-37S
  26. The truth about carbs. NHS Choices
  27. Noto H, Goto A, Tsujimoto T, Noda M. Low-carbohydrate diets and all-cause mortality: a systematic review and meta-analysis of observational studies. PLoS One. 2013;8(1):e55030. [full text]
  28. Westerterp-Plantenga MS, Lemmens SG, Westerterp KR. Dietary protein – its role in satiety, energetics, weight loss and health. Br J Nutr. 2012 Aug;108 Suppl 2:S105-12
  29. WbMD High Protein, Low Carb Diets Explained
  30. NHS Choices. Red meat and the risk of bowel cancer
    http://www.nhs.uk/Livewell/Goodfood/Pages/red-meat.aspx /
  31. Ginty F. Dietary protein and bone health. Proc Nutr Soc. 2003 Nov;62(4):867-76
  32. Mazidi M, Katsiki N, Mikhailidis DP, Sattar N, Banach M Lower carbohydrate diets and all-cause and cause-specific mortality: a population-based cohort study and pooling of prospective studies. Eur Heart J. 2019 Sep 7;40(34):2870-2879
  33. Seidelmann SB, Claggett B, Cheng S, Henglin M, Shah A, Steffen LM, et al. Dietary carbohydrate intake and mortality: a prospective cohort study and meta-analysis. Lancet Public Health. 2018 Sep;3(9):e419-e428 [full text]
  34. Garber AK, Lustig RH. Is fast food addictive? Curr Drug Abuse Rev. 2011 Sep;4(3):146-62
  35. Esmeijer K, Geleijnse JM, de Fijter JW, Kromhout D, Hoogeveen EK. Dietary protein intake and kidney function decline after myocardial infarction: the Alpha Omega Cohort. Nephrol Dial Transplant. 2019 Feb 14.
  36. Jhee JH, Kee YK, Park S, Kim H, Park JT, Han SH et al. High- protein diet with renal hyperfiltration is associated with rapid decline rate of renal function: a community-based prospective cohort study. Nephrol Dial Transplant. 2019 Jun 7.
  37. Kalantar-Zadeh K, Kramer HM, Fouque D. High-protein diet is bad for kidney health: unleashing the taboo. Nephrol Dial Transplant. 2019 Nov 7 [full text]
  38. Budney AJ, Emond JA. Caffeine addiction? Caffeine for youth? Time to act! Addiction. 2014 Nov;109(11):1771-2
  39. H van der Vaart, D S Postma, W Timens, N H T Ten Hacken. Acute effects of cigarette smoke on inflammation and oxidative stress: a review. Thorax 2004;59:713-721
  40. Cesaroni G, Forastiere F, Stafoggia M, Andersen ZJ, Badaloni C et al. Long term exposure to ambient air pollution and incidence of acute coronary events: prospective cohort study and meta-analysis in 11 European cohorts from the ESCAPE Project. BMJ. 2014 Jan 21;348. [full text]
  41. Campbell PT, Gross MD, Potter JD, Schmitz KH, Duggan C, McTiernan A, Ulrich CM. Effect of exercise on oxidative stress: a 12-month randomized, controlled trial. Med Sci Sports Exerc. 2010 Aug;42(8):1448-53. [full text
  42. Maxwell S, Greig L. Anti-oxidants– a protective role in cardiovascular disease? Expert Opin Pharmacother. 2001 Nov;2(11):1737-50
  43. Bjelakovic G, Nikolova D, Simonetti RG, Gluud C. Antioxidant supplements cannot be recommended for gastrointestinal cancer prevention Cochrane Database of Systematic Reviews 2008
  44. Daily Mail 22 December 2005. Extract from Nutrition for Dummies
  45. NHS. Miracle food, myths and the media. 2011
  46. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database of Systematic Reviews 2012, Issue 2. Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C
  47. Goodman M, Bostick RM, Kucuk O, Jones DP. Clinical trials of antioxidants as cancer prevention agents: past, present, and future. Free Radic Biol Med. 2011 Sep 1;51(5):1068-84
  48. Kristal AR, Darke AK, Morris JS, Tangen CM, Goodman PJ, Thompson IM, et al. Baseline Selenium Status and Effects of Selenium and Vitamin E Supplementation on Prostate Cancer Risk. J Natl Cancer Inst. 2014 Feb 22
  49. Li J, Dong HL, Jie H, Tabung FK, Li Y, Bhupathiraju SN, Rimm EB et al. Dietary Inflammatory Potential and Risk of Cardiovascular Disease Among Men and Women in the U.S. J Am Coll Cardiol. 2020 Nov, 76 (19) 2181–2193
  50. Proinflammatory Dietary Pattern Linked to Higher CV Risk. Medscape 3 November 2020.
  51. Heneghan C, Howick J, O’Neill B. The evidence underpinning sports performance products: a systematic assessment. BMJ Open 2012;2:e001702. http://bmjopen.bmj.com/content/2/4/e001702.short
  52. Wolstenholme JT, Rissman EF, Connelly JJ. The role of Bisphenol A in shaping the brain, epigenome and behavior. Horm Behav. 2011 Mar;59(3):296-305. [full text]
  53. Noakes TD. Commentary: role of hydration in health and exercise
  54. Needleman I, Ashley P, Petrie A, Fortune F, Turner W, Jones J, Niggli J, Engebretsen L, Budgett R, Donos N, Clough T, Porter S. Oral health and impact on performance of athletes participating in the London 2012 Olympic Games: a cross-sectional study. Br J Sports Med. 2013 Nov;47(16):1054-8. [full text]
  55. Athletes have poor teeth despite brushing. BBC News 29 August 2019
  56. Additives or E numbers. Foods Standards Agency
  57. Just how dangerous are those E numbers? Daily Mail
  58. Bateman B, Warner JO, Hutchinson E, Dean T, Rowlandson P, Gant C, et al. The effects of a double blind, placebo controlled, artificial food colourings and benzoate preservative challenge on hyperactivity in a general population sample of preschool children. Arch Dis Child. 2004 Jun;89(6):506-11. [full text]
  59. Millichap JG, Yee MM. The diet factor in attention-deficit/hyperactivity disorder. Pediatrics. 2012 Feb;129(2):330-7. [full text]
  60. Smith-Spangler C, Brandeau ML, Hunter GE, Bavinger JC, Pearson M, et al. Are organic foods safer or healthier than conventional alternatives?: a systematic review. Ann Intern Med. 2012 Sep 4;157(5):348-66
  61. The Soil Association. Fertilisers
  62. Reuters. Analysis: E.coli outbreak poses questions for organic farming. 6th June 2011
  63. Organic Food FAQ. Health and Safety Executive
  64. 6 myths about organic food. WebMD
  65. The Organic Label
  66. Bradbury KE, Balkwill A, Spencer EA, Roddam AW, Reeves GK, Green J, et al. Organic food consumption and the incidence of cancer in a large prospective study of women in the United Kingdom. Br J Cancer. 2014 Apr 29;110(9):2321-6
  67. Baudry J, Assmann KE, Touvier M, Allès B, Seconda L, Latino-Martel P et al. Association of Frequency of Organic Food Consumption With Cancer Risk: Findings From the NutriNet-Santé Prospective Cohort Study. JAMA Intern Med. 2018 Dec 1;178(12):1597-1606
  68. Barański M, Rempelos L, Iversen PO, Leifert C. Effects of organic food consumption on human health; the jury is still out! Food Nutr Res 2017; 61(1): 1287333. [full text]
  69. GM crops don’t kill kids. Opposing them does. Matt Ridely. The Times. 1st August 2013
  70. Ben Webster. Opponents of GM crops are a bunch of lunatics, say scientists. The Times. 4th August 2014
  71. Chief scientist is forced out after green campaign. The Times. 14th November 2014
  72. Juncker has given in to the lobbyists from Greenpeace. The Times, 14th November 2014
  73. Greenpeace accused over child deaths. The Times 1st February 2014
  74. Gene Editing by Judith L. Fridovich-Keil. Britannica.
  75. The rise and fall of Sunny Delight. Jennifer Clayton. BBC News. 3rd December 2003
  76. My net diary
  77. Which? Smoothies
  78. Is your fruit smoothie as healthy as you think? Which? December 2012
  79. Coca-Cola’s secret influence on medical and science journalists. Paul Thacker. BMJ 2017;357:j1638
  80. Serodio PM, McKee M, Stuckler D. Coca-Cola – a model of transparency in research partnerships? A network analysis of Coca-Cola’s research funding (2008–2016) Public Health Nutr. 2018 Jun; 21(9): 1594–1607 [full text]
  81. Greenhalgh S. Soda industry influence on obesity science and policy in China. J Public Health Policy. 2019 Mar;40(1):5-16

Site Index

This website is now completed, although I shall continue to do updates. The following list shows the sections or chapters. Just click on the topic in blue to go to that part of the site.

1 Introduction
2 A Very Brief History of Science And Medicine
  Fundamentals of Medical Science
3 Finding Good Medical Advice and Evidence Based Medicine
4 Randomised Controlled Trials
5 Cohort or Longitudinal and Epidemiological Studies
6 Qualitative Research
7 Basic Maths in Medical Research and Decision Making
8 How Good is the Evidence?
9 Ethics in Practice and Research
  Public Health Issues
10 Screening Programmes
11 Fake News and Vaccine Scares
12 Electronic Cigarettes (E-Cigarettes)
13 Motor Vehicle Emissions, Air Pollution and Health
14 COVID-19. What You Need to Know
15 Who is at Risk from COVID-19
16 What we Must Learn from the COVID-19 Pandemic
17 Basics of Nutrition
18 Exercise, Obesity and Diets for Weight Loss
19 Diets and Nutrition for Health and Fitness
20 Supplements
  Complementary and Alternative Medicine
21 Introduction to Alternative Healthcare
22 Homeopathy
23 Acupuncture
24 Manipulation of the Spine
25 Reflexology
26 Herbal Remedies
27 Other Natural Products
28 Chelation Therapy
29 Hypnosis
30 Other Modalities of Complementary and Alternative Medicine
  Some Controversial Diseases
31 Fibromyalgia
32 Chronic Fatigue Syndrome (CFS) or Myalgic Encephalitis (ME)
33 Systemic Candidiasis and Leaky Gut Syndrome
34 Mobile Phones, Masts, Wi-Fi and Electro-sensitivity
  The Environment
35 Global Warming and Climate Change
36 Alternative Energy
  Some Final Thoughts
37 Still Searching for the Age of Reason