According to our scientific establishment, and the respectable media, cancer is caused by a wide range of factors. These factors include many things that we have no control over. In particular, our genetic history and our environment are said to play a major role in cancer formation. It’s therefore effectively a matter of pot-luck whether one of us gets cancer or not during our lifetime.To put it bluntly, we can’t do anything about getting cancer; it’s just a roll of the genetic and environmental dice. To quote from the Wikipedia page on cancer:

The majority of cancers, some 90–95% of cases, are due to genetic mutations from environmental factors. The remaining 5–10% are due to inherited genetics.

I’ve looked into this matter in some depth and I have a strong suspicion that this is simply not true. Instead, there is a lot of evidence that what we eat and drink has an enormous influence on whether or not we get cancer, and whether or not we can survive it. I’ll split the rest of this article into several sections, focussing on different, important foods that the large majority of us eat.


The first piece of evidence I discovered, during my research, was that a diet high in animal protein carried with it a high likelihood of the person getting cancer. The excellent documentary Forks over Knives puts forward this case in a thorough and accessible manner. The documentary isn’t simply a series of anecdotes. It references a lot of scientific research into the connection between animal protein and cancer.

The documentary’s conclusions are backed by other studies. For example, this Guardian article states that a US study of six-thousand people, the National Health and Nutrition Examination Survey (NHANES), concluded that:

High levels of dietary animal protein in people under 65 years of age was linked to a fourfold increase in their risk of death from cancer or diabetes, and almost double the risk of dying from any cause over an 18-year period.

That is a very big increase in risk. The NHANES study makes it clear that a high animal protein diet can be as dangerous to a person’s health as smoking.

Another study, commissioned by the World Health Organisation group, the International Agency for Research on Cancer, made the following statement in their press release IARC Monographs evaluate consumption of red meat and processed meat, available here as a pdf:

The experts concluded that each 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by 18%.

Both pieces of evidence fit the Forks over Knives documentary’s comment that a diet that contains more than 5% animal proteins significantly increases the risk of cancer. Fortunately, the IARC say that reverting to a diet low in animal protein can reverse the problems caused by the high-animal-protein exposure. In other words, the damage can be undone.

There also seems to be links between cancer and inflammation, which makes sense as inflammation is a result of the body being stressed by something toxic to its system, or simply alien. In some cases, elements in the meat, such as its proteins or the animal hormones still floating around in it, might alarm our bodies. In other cases, the presence of the animal proteins in our guts can cause the proliferation of bacteria, and its by-products, that we don’t want in our bodies in large amounts. For example, this New Scientist magazine article reports on some very interesting research. To quote:

Switching to a diet based exclusively on animals or plants triggers rapid changes to the microbes that rule your gut. This knowledge could help fine-tune diets to improve health, as well as reduce the risk of illnesses like inflammatory bowel disease.

The article goes on to say that when someone has switched to, or is on a largely plant-based diet, a particular bacteria dominates in their gut. This bacteria produces a fatty-acid known as butyrate, which is known to reduce inflammation. This fatty-acid is also, ‘thought to reduce colorectal cancer risk by boosting the health of cells lining the intestines and prompting cancerous cells to self-destruct.’ (quoting from the article). By comparison, the bacteria that dominates in the gut of someone on a high animal-protein diet – Bilophila wadsworthia – is linked with inflammatory bowel disease.

As we can see from the evidence so far, consuming more than a small amount of animal proteins has a lot of negative, knock-on effects. We’ve already seen the risk factors increase with calcium loss, irritable bowel syndrome, cancer and diabetes. Effectively, meat should be seen as something alien to our bodies and something we should only eat sparingly. One way of looking at the issue is to remember that our digestive system is little different from chimpanzees. Whatever they eat, we should be eating too. Anything they don’t eat, we should only eat in small amounts. If we ignore that rule, our bodies immediately suffer problems.

The fundamental damage to our bodies from meat, amongst other stresses, can be see in a study by the Preventive Medicine Research Institute in Sausalito, California. They carried out the study to see if diet and lifestyle could reduce or revert cell-ageing in 10 men in their early sixties with prostate cancer. To quote from the New Scientist article on the study:

[The subjects were] ‘asked to follow a strict healthy-living regime rather than take a course of drugs. They ate a meat-free diet, did exercise and yoga daily and went to weekly group therapies. After five years, the telomeres on a type of white blood cell were 10% longer on average in these men. In contrast, 25 men with the same condition who kept to their usual lifestyles saw the telomeres on these cells shrink by an average of 3% over the same period.’

Telomeres are key pieces of our genetic code. They sit at the end of the chromosomes in our cells, the DNA sections that hold information on how our cells should function. Telomeres seem to act as our biological clock; they shorten in length as our cell ages, telling our bodies how old our cells have become, and when they should be broken up. There is extensive evidence that indicates that people with short telomeres are likely to contract several major diseases – heart disease, dementia and cancer – and live shorter lives. In other words, if our cell-clocks run down fast, it’s a sign that we’re in cellular trouble.

Before we move on to the next foodstuff, it’s worth noting that preserved meats can have other negative health effects. For example, preserved meats can contain toxic amines, such as histamine, cadaverine and putrescence (you can guess why they’re called that) which occur as the meat proteins break down. If a person’s digestive system is low on certain key enzymes known as Mono-amine Oxidase Inhibitor or MAO, then those amines can make that person moody, aggressive, tearful and generally a mess. I cover this in more detail in this article, meat, amines and mood.


It’s worth remember that animal protein isn’t just meat. Here is the West, we also consume a lot of dairy products, particularly milk. If the evidence in Forks over Knives is correct, then we should also be wary of consuming too much milk. This New Scientist article reports on a health study carried out on tens of thousands of people in Sweden. The study ran for over 20 years and focussed on milk consumption by adults. It found that:

‘the more milk people drank, the more likely they were to die or experience a bone fracture during the study period.’

The study also found that women who reported that they drank three-or-more glasses of milk a day had almost double the risk of dying during the study period as those who reported only drinking one.

The results of the Swedish study flies in the face of the traditional view of milk; that it’s a healthy food and that it helps our bones because it contains calcium. This view may need to be reviewed. As far as I can remember, the Forks over Knives documentary gives an explanation that fits the Swedish study very well. The documentary explains that it’s true that milk does contain calcium but our bodies can’t absorb that calcium because we don’t have the appropriate enzymes. This is mostly because milk is for calves, not for us; they do have the enzymes. As a result, the milk isn’t fully broken down in our gut. Its proteins and other constituent parts enter our bloodstream where they can create an acid environment. The ph-balance of our blood, the balance between acid and alkali, must be maintained within tight values, for us to stay healthy. Our body therefore has to rectify that acid imbalance, caused by the milk proteins. It does that by drawing calcium from our bones, which neutralise the acid excess. The bizarre result of this is that drinking milk actually causes us to lose calcium from our bones, not gain it.

The milk-calcium paradox shows that we need to be very careful what the food industry recommends to us. They tell us that milk contains calcium and we need calcium for our bones. These are both true statements. What the food industry doesn’t mention is that we can’t absorb the calcium in milk. We’re far better off gaining our calcium from greens and spinach, since we can absorb the calcium effectively from vegetables. This makes perfect sense, genetically. We’ve been eating vegetables for millions of years; our gut is excellent at digesting such food. By comparison, we’ve only been drinking cow’s milk for a few thousand years, partly because most of us had the luck of possessing a relatively new enzyme that could break down lactose, the sugar in milk.


Most people like toasted bread, or toast for short. Many people also like chips or fries. They also seem harmless fun, as they’re nothing more than starches heated to high temperature. Unfortunately, scientific research shows that this may not be the case.

Many years ago, a research team in Scandinavia were told about an odd phenomenon; a herd of cows were showing signs of being brain-damaged. The cows should have been perfectly healthy but for some reason, they’d been showing symptoms of mental injury, balance problems, erratic behaviour and other, associated issues. The researchers eventually tracked down the cause of the cows’ distress; the cows were drinking from a stream that had been contaminated by acrylamide, leaking from a nearby factory.

The toxicity of acrylamide was a new thing to these scientists, and so they followed up the case, studying the effect of this chemical in more detail. The molecule isn’t good for our bodies. As this scientific paper, ‘Acrylamide: its metabolism, developmental and reproductive effects, genotoxicity, and carcinogenicity‘ makes clear, acrylamide binds to our DNA and can cause genetic abnormalities. There is also evidence of humans suffering similar problems to the cows. This scientific paper, Two case reports of neurological disease in coal mine preparation plant workers, investigates what happened to two mine-workers who were regularly exposed to an acrylamide polymer:

The patients had worked in different coal preparation plants in southern West Virginia for over 10 years and had exposure to an acrylamide polymer flocculent contaminated with acrylamide monomer. Both patients had no instruction on proper use of, or the dangers of, acrylamide and were not given adequate safety equipment. Patient A developed Parkinsonism and Patient B peripheral neuropathies with a neurogenic bladder.

There is therefore good evidence that acrylamide isn’t good for us. Scientists therefore looked for everyday sources of acrylamide, other than simply factory effluent, or mining chemicals, to make sure the general public weren’t being exposed to it on a daily basis. They discovered something disturbing; any food that is browned or turned golden by heating will contain acrylamides. At the high temperates of roasting and grilling, organic molecules in the food, particularly refined starch, is chemically transformed into acrylamide.

It’s worth noting at this point that there is a lot of evidence that the amount and form of acrylamide in toasted or golden-brown food isn’t a big risk for us. According to the studies, a fish and chip supper once a month isn’t a death sentence, but science does tell us that negative effects do accumulate. Just as with milk and lots of meat, the more we stray from the diet our mammalian ancestors consumed, such as the chimpanzees, the higher the risk of damage to our bodies from that food.


In 2014, Dr David Perlmutter wrote a fascinating non-fiction, science book called Grain Brain. In the book, he describes how eating lots of grains is a bad idea for us, as human beings. We are not built to consume grains. This is hardly surprising, since the practice of growing large amounts of grain to feed a human population is only a very recent development, at least in terms of the human species. Before we started growing grains, in around 4,000 BC, we existed on a hunter-gatherer diet. This diet would have consisted of very fresh meat, fresh fish, nuts, leafy greens and seasonal berries, again similar to chimpanzees (with the exception of fish). We would have eaten some carbohydrates as part of our hunter-gatherer diet, in the form of tubers, but we would not have eaten grasses in any significant amount, such as wheat, rye, barley and rice. Our digestive systems are built to digest a non-grain diet. After the rise of civilisation, we began consuming large amounts of starch. This is a useful plant-energy storage system, but when we consume it, it is quickly broken down into sugars in our gut. If we combine this with our consumption of actual sugars, not just sugar-cane but also  concentrated fruit sugars, it’s clear that this must be a severe shock to our digestive systems, built as they are to expect only low levels of any form of sugar.

Dr Perlmutter explains in his book that our body has a very hard time dealing with our intake of carbohydrates and sugars. Meals heavy with these foods inevitably cause a rapid increase in the amount of sugar in our blood. Our body must then work hard to remove the sugars from our blood system. It does this by pumping out insulin, which shepherds the sugar into our cells. But these cells can only take in so much sugar, and they soon begin to close the gates to more sugar coming in. As a result, even though our pancreas has pumped out lots of insulin, the sugar hasn’t left our blood system. This is bad for our body, since sugar is a toxin and if it’s swilling around our blood-system, and not being taken up by cells, then many of us will get blood pressure problems, heart problems, circulation problems and other chronic diseases. In addition, there is the threat of diabetes, probably the most well-known disease caused by over-consumption of sugar.

Unfortunately, as Dr Perlmutter explains, there is a further problem with a diet high in carbohydrates and sugar; inflammation in the brain, leading to long-term cognitive damage. It’s worth noting, at this point, that grains aren’t simply starch bags. They also contain gluten. Gluten has an interesting property. When we consume it, in bread for example, it breaks down in our gut and forms peptides. These molecules have a strong effect on our brains. They can give us a warm, fuzzy feeling, because they bind to opiate-type receptors in our brain. This might seem hard to believe but, in principle, any gluten-containing foodstuff, such as bread, acts like an opiate-drug. This effect may not have been lost on the food industry. Over time, they have chosen and refined flours that have had a higher and higher gluten level. As a result, something seemingly as benign as a pizza and coke is actually a smorgasbord of psychoactive drugs, especially if we remember that casein, present in cheese, is also psychoactive.

One perceived problem with moving away from grains is that eating natural fats will make us fat. Dr Perlmutter explains, in great detail in his book, that people don’t get fat on a fat and protein diet, they get fat on a sugar and carbohydrates diet. This is because their body has to turn the sugars into fats and store them to get them out of the bloodstream. By comparison, once you’re on a fat and protein diet, the body burns the fats in its cells naturally and sends your signals that you’re full. This approach to our body gaining energy is known as ketosis. A ketosis diet is often recommended to prevent certain cancers, since cancer cells can’t burn fats, they can only burn sugars.

For a long time, the food industry has been persuading us that diets high in fats are dangerous, and also that high cholesterol is dangerous. Dr Perlmutter explains in his book that cholesterol is actually a vital component of our body; it is needed to transfer fats into our brains, which are mostly made of fat. He reports in his book that studies have shown that people with low cholesterol, including those taking statins, have a much higher risk of Alzheimers and other cognitive degeneration illnesses. He explains that damaged cholesterol, oxidised by sugar and free radicals, is dangerous to the body but the fault lies with the carbohydrate diet, not the cholesterol itself.


There are a lot of scientific studies showing that sugar is bad for us. This article has already talked about sugar’s connection with diabetes and other chronic diseases. Its negative effect on our bodies is palpable. For example, this Guardian article, Soft drinks, including sugar-free, linked to increased risk of early death, explains the link between soft-drink consumption and a higher risk of dying. To quote from the article:

The results show 9.3% of those who drank less than one glass of soft drink a month died during the study, compared with 11.5% of those who drank two or more 250ml glasses a day. The team say that once factors such as body mass index, diet, physical activity, smoking and education were taken into account, that translates to a 17% higher risk of death among those consuming two glasses a day compared with those drinking less than one glass a month.

It’s worth noting that artificially sweetened drinks were also associated with a higher risk of death. There are two possible reasons for this. Firstly, that artificial sweeteners are toxic to the body and secondly, that if we consume artificial sweeteners, this throws our body’s hormone signalling system into disarray, due to these false ‘signals’. As a result, our natural appetite reduction is lost and we feel peckish more of the time. As a result, by consuming sweeteners as an alternative to sugar, in drinks and beverages, we actually prime ourselves to consume more food and we end up eating more starches, which turn into sugar in our guts.

The studies also show a connection between sugar consumption and cancer. Another Guardian article, entitled, Sugar in fruit juice may raise risk of cancer, reports on a study published by the British medical journal, the BMJ. To quote from the article:

The study, carried out in France, is the first substantial piece of research to find a specific association between sugar and cancer. Sugary drinks such as colas, lemonade and energy drinks have been linked to obesity, which is a cause of cancer, but the French researchers suggest there could also be other reasons sugar could trigger it. The study, published in the BMJ, finds the association with cancer is just as strong with fruit juices as it is with colas. “When the group of sugary drinks was split into 100% fruit juices and other sugary drinks, the consumption of both beverage types was associated with a higher risk of overall cancer,” it says.

This isn’t a great surprise, since the relationship between sugar and cancer has been known for a long time. It was pointed out and defined as a theory by a Nobel Prize-Winner, the brilliant physiologist Otto Warburg. Warburg won the Nobel Prize for Physiology and Medicine in 1931. During his life, he had a very straightforward view of the cause of cancers. To quote from his Wikipedia entry:

“Warburg hypothesised that cancer growth is caused by tumour cells generating energy (as, e.g., adenosine triphosphate / ATP) mainly by anaerobic breakdown of glucose (known as fermentation, or anaerobic respiration). This is in contrast to healthy cells, which mainly generate energy from oxidative breakdown of pyruvate. Pyruvate is an end product of glycolysis, and is oxidised within the mitochondria. According to Warburg, hence, cancer should be interpreted as a mitochondrial dysfunction.”

To quote from the man himself:

Cancer, above all other diseases, has countless secondary causes. But, even for cancer, there is only one prime cause. Summarised in a few words, the prime cause of cancer is the replacement of the respiration of oxygen in normal body cells by a fermentation of sugar.

It’s worth noting, at this point, that the appearance of cancers in our body is actually a normal event. Micro-cancers appear all the time in our bodies. Our immune system gets rid of them on a regular basis. But it is the unstopped development of these micro-cancers into macro-cancers that is unnatural. The presence of sugar fermentation in our cells could be why this happens. Their presence creates an unnatural cellular environment which supports such unnatural cellular activities as cancer development. Our immune system can deal with this problem, if it is put into an ‘alarm mode’, during a fever. For more on that, please read my Fever: A cancer cure article.

Warburg’s insight was not lost to science. More recently, Dr Robert Lustig, Professor of Pediatrics in the Division of Endocrinology at the University of California, San Francisco, has been working tirelessly to point out the connection between sugar and major health problems such as obesity and various diseases, writing books such as Fat Chance, the hidden truth about sugar, obesity and disease. Dr Lustig explains, in his books and videos, that fructose, a fruit sugar present in many foodstuffs, especially in the form of High Fructose Corn Syrup, is metabolised in our bodies into aldehydes, which are damaging to our livers and other organs. In that form, it is as dangerous as alcohol.


At this point in this article, it’s worth looking again at the Wikipedia statement about the causes of cancer:

The majority of cancers, some 90–95% of cases, are due to genetic mutations from environmental factors. The remaining 5–10% are due to inherited genetics.

Hopefully, this article has shown that the Wikipedia statement is plain wrong. It encourages people to believe that what they eat and drink is irrelevant to their risk of developing cancer when, in fact, our diet has a major effect on our cancer risk, as well as our risk of developing many chronic diseases. There is also a major logical flaw in believing that we are genetically predisposed to cancer because if that was the case, why was it not weeded out through natural selection? A far more likely scientific explanation is that we are consuming food that is toxic to our bodies and that is causing the cancers.

To put it simply, the further we stray from our hunter-gatherer diet, the worse it gets. If we want to avoid chronic health problems and a lot of suffering in our later lives, we need to transform our diets.