Diet has an impact on health and affects the risk of disease1. Over the last few decades biochemical and other sciences, from neural to gastric, have made impressive contributions to our knowledge2. Never before have scientists known so much about food and nutrition. Unfortunately much of this knowledge is not reported by the popular press and news outlets because it is technical, mundane and statistical in nature. The average consumer mostly hears only the sensational claims of pseudoscientific sham researchers and promoters, which are often paid for and orchestrated by the rich food industry itself. The two most misleading sources of information are reports based on single-studies and TV adverts. Most people are ill-informed about diet and health as a result of this.
There have been a long series of temporarily popular fad diets which limit food intake to a specific range of items, sometimes cutting out essential fats and proteins completely. They emphasize rapid short-term change at the expense of medium and long-term issues. Of the independent scientific studies on fad diets, supplements, mega-vitamins and similar highly-hyped abnormal sources of nutrition, all have found them to be useless and sometimes actually harmful. The National Health Service (UK) warns that "many fad diets are based on dodgy science or no research at all, prescribing eating practices that are unhealthy and can make you ill"3. The boring truth is that only well-rounded diets are truly effective at long-term weight management with only the very basic advice being effective: cut down on fats and salts, cut down on sugary and fizzy drinks, and eat plenty of wholegrain food, fruit and vegetables (5 portions a day), and drink ordinary water.4,3
Fads rely on testimonials and public-relations tricks to make themselves sound effective and claims are often based on (easily biased) single-studies rather than on independently verified and duplicated scientific trials. The mass media love reporting on these single-studies as their claims are often outlandish and celebrity endorsements boost a fad diet from time to time. Fad diets distract people from sensible eating habits. Rather than accept enthusiastic praise from soap stars, models and newspaper advertisements, it is doctors and the medical profession that we should trust to keep us informed. Let's stop falling for these tricks!
There are a lot of fads around. The problem is that they're mostly all new. In other words, today's fads will soon disappear over a scale of years, or after a decade or two. They'll be forgotten, and all those who claimed that the fad worked will have moved on to something else. If food fads worked, then, certain ones would prove popular for all time. That they come and go with such frequency (and each with such acclaim) means that they don't work despite people thinking that they do, and that their feel-good factor is only a psychological result of promotions and PR. Word of mouth and anecdotal evidence are two of the most prevalent causes of human error (see Errors in Thinking: Cognitive Errors, Wishful Thinking and Sacred Truths).
The Fletcherite Method (1890s until 1910s)5: Food must be chewed between thirty to seventy times, until it is purely liquid. This makes people much younger. The reasons and theory behind this never made much sense. It was a popular and common method, and, it might have been on to one little truth, which of course was completely missed by its proponents: eating more slowly makes people eat less. This is because as we digest food, we feel fuller. Eat more slowly, and we feel full earlier into the meal, so, we eat less. A recent "fad" uses this truth as its only justification (it is, really, correct): if you eat with your left hand (if you're right handed), then you eat less! Good for helping to control weight, simply because you eat slower. Anyway, this wasn't part of the justification Horace Fletcher gave in his books on his crazy excess-chewing method.
The Hayite Diets were started by medical Dr Howard Hay in the 1930s (or earlier). "According to Dr Hay, almost all bodily ills are the result of "acidosis." This is turn is caused by (1) too much protein, (2) too much adulterated food, like white bread, (3) combinations in the diet of protein and carbohydrates, (4) retention in the bowels of food beyond twenty-four hours after eating". In reality, none of those things cause acidosis. Needless to say, despite all of the books, seminars and endless acclamations by satisfied dieters, no-one today has heard of those crazy requirements for health. There is a final irony, sealing that fact that diets really ought to be worked out by qualified experts, not merely by people who think they're clever, and, then subjected to the trials of scientific peer review: For Dr Hay "also recommends frequent fasting, apparently unaware that fasting really causes acidosis".6
As investigator Martin Gardner points out, "It would take many volumes to discuss all of the tonics, vitamin products, mineral salts, and other miracle foods which in recent years have made fortunes for their promoters. One manufacturer even put vitamins in soap, where they are about as useful as the hormone that appeared in a nationally advertised brand of face cream or the magnetic properties recently acquired by a certain make of razor blade. Chlorophyll seems to be the latest wonder compound turning up everywhere to do everything"7.
The problem is a lack of skeptical thinking, mass gullibility, desperation and wishful thinking, combined with magical thinking of the kind that allows all kinds of quack remedies and quirky products to survive on the marketplace, and a completely lack of fact-checking and scientific knowledge on the behalf of news outlets who often run articles on these amazing sounding fads.
The NHS warns that the following diets don't work and are based on faulty science, and if followed, can lead to harm and decreased health:3
“[A]fter spending hundreds of millions of dollars on scientific controlled trials, it is now clear that megavitamins do not work.”
Dr Spector in Skeptical Inquirer8 (2009)
“[U]ntrue claims that certain nutrients and nutraceuticals reduce cardiovascular risk and prevent cognitive decline or cancer steer patients away from safe, proven treatments that are often cheap and generic. For example, generic aspirin, ACE inhibitors, and stains have been unequivocally proven to decrease cardiovascular risk and death in selected populations.”
Dr Spector (2009)
The supplements industry is well-known amongst scientists and government-officials to be worthless and sometimes harmful9. Its success is based purely on public relations to such an extent that several countries have considered banning bottled supplements altogether. Although the contents of supplements are often the right chemicals that our bodies need, in most cases we simply cannot metabolize or use the chemicals in concentrated pill form, making them effectively useless. This is why most supplements-adverts are very careful not to claim that they can improve health or diet, but, they merely list their ingredients or give the results of opinion-polls rather than provide scientific evidence.
The fish oil craze ("brain food!") centers on omega-3 oils. Dr Goldacre reports with observant glee that the benefits of omega-3s must be false, because "we do not have an epidemic of thick vegetarians"10. In other words, any effect must be considered as part of overall diet, and, the effect is small.
There are two routes by which these industries harm people's health. They can do so directly, causing medical problems as do some 'megavitamins' and fad diets ("megavitamins" are normal vitamins in massive doses. Such dosage is not beneficial and is sometimes harmful). Or they can harm indirectly by making people feel that their diet is good enough due to the supplements, when in reality they still need to improve their diet (because supplements do not work).
The particular success of the dietary supplements industry compared with its particular ineffectualism was one of the reasons that prompted Dr Spector to report on the issue in the Skeptical Inquirer:
“It is worth noting that the nutraceutical (supplement) industry is a multi-billion-dollar enterprise. [...] Focusing on the lack of scientific rationale for so many nutritional claims, many people ask why and how this sad state of affairs developed.”
Dr Spector (2009)
The causes of such success are discussed later on this page.
Some people take up ridiculous diets or regimes instead of seeking medical treatment or using proven methods of health improvement, and this has been noted by those in the medical world. Two things are needed before such diets should be considered worthwhile: (1) Scientific papers published in peer-reviewed journals (as per the Scientific Method), (2) long-term (at least 2-yr) studies on human subjects and (3) that the diet's inventors and/or supporting scientists are not being paid by elements of the food industry itself. Unfortunately, I know of no popular diet that has a track record in anything other than good advertising rather than good science.
“Do weight-loss diets in obese people work? None work well. On average, over the long term, obese humans do not lose much weight on voluntary low-calorie diets of any kind. (There are of course a few obese individuals who have "self discipline" and can lose weight and keep the weight off. Their "secret" is obscure.) There is, however, some evidence that low-carbohydrate diets "work" best at least for periods up to one year, but this has not been replicated in a two-year study. Notwithstanding thousands of weight-loss articles and books, there has been very little progress in this area outside of surgical intervention.”
Dr Spector (2009)
“The theory behind antioxidant claims sounds very compelling. Oxidants are chemicals (free radicals, also called reactive oxygen species or ROS) that are the products of metabolism; they are highly reactive and can cause damage to proteins and cells. This damage is a major contributor to aging and disease. Antioxidants neutralize these free radicals and prevent damage.
Unfortunately, medical science is rarely so clean and simple. [...] Twenty years ago this was the state of our knowledge of ROS [...] however as research continued we learned [that] the body has evolved a natural defense against the onslaught of ROS. These compounds are called free radical scavengers or antioxidants (such as the protein superoxide dismutase and some vitamins like C and E) and their job is to gobble up ROS before they can damage cells.
In addition ROS actually serve a purpose in the body, for example, as signals to cells or as neurotransmitters (nitric oxide). In fact, the body has evolved a balanced and complex system to maintain homeostasis between ROS and antioxidants. Influencing that system by taking large amounts of exogenous antioxidants may not be such a good idea. In other words, if a balance between ROS and antioxidants has evolved, there is no reason to believe that there are any benefits to tipping the scales in one direction - towards antioxidants. In fact, doing so may cause harm.
What does the actual clinical evidence show? [...] Overall, the evidence is ambiguous and does not support a benefit for treatment [... and] actually suggests the potential for harm. A comprehensive review published in 2008 concluded: 'We found no evidence to support antioxidant supplements for primary or secondary prevention. Vitamin A, beta-carotene, and vitamin E may increase mortality' (Bjelakovic et al. 2008).”
Dr Novella (2013)
According to some, the opposite of intensively produced crops and GM food is 'organic' food, but for the record all three are organic and all are composed of natural biological molecules.
“There are many mysteries about what constitutes organic food. If a banana is squashed and its juice extracted to produce 'banana flavouring', it can be analysed and shown to be the chemical amyl acetate. However, if one produces amyl acetate by adding vinegar to amyl alcohol, it cannot be called 'organic'. It is the same chemical [... but] it is presumed to be bad. [...] A walk around the organic shelves of a supermarket leaves one amazed at the gullibility of its patrons. There is no evidence that organic food is better for you than any other food. The Advertising Agency investigated the claim by organic famers that their produce was 'healthier' and concluded that such a claim could not be justified.”
"Panic Nation: Unpicking the Myths We're Told About Food and Health"
Feldman & Marks (2005)11
Organic foods should mean "produced without chemicals", but, organic farms still do use a range of chemicals. They tend to prefer ones that (they claim) have a better track record with regards to environmental damage. Organic foods bring with them higher chances of poisoning, salmonella, disease and impurities and often use chemicals that are somewhat less tested than those that intensive farmers trust. There is an outcry against GM food not by the scientists themselves, but from the farmers and the popular media. When Tescos decided to remove GM food a few years ago, it was due to pressure from activists, not as a result of health issues. Despite known health issues, Tescos and other supermarkets have not removed organic food!
“Organic farming raises risks of faecal contamination not only of food but also of waterways, food poisoning, high levels of natural toxins and allergens, contamination by copper and sulphur-containing fungicides, production of diseased food, low productivity, and creation of reservoirs of pests and diseases. Cars, cigarettes, stepladders and playing sports are dangerous - eating GM food is not. Deliberately pejorative language is obscuring the debate and encouraging people to pre-judge the issues before they have heard all the facts.”
Professor Hillman (2000)12
So far we have talked about modern organic farming - it must be remembered that the very concept was not the result of scientific testing, nor was it the result of observations on human health. Rodale, in the USA, was a prime mover behind what we now call organic food, calling it organic farming, and it was riddled from the outset with irrationality and superstition. Amongst other principles (i.e., cooking food is bad) he sternly upheld the belief that food must be grown "God's way", and that included using only animal and vegetable fertilizers, otherwise, he asserted, plants would not produce enough nutrition. Yet "soil and nutrition experts tell us that if plants grow at all, their composition tends to remain essentially the same, with respect to mineral and vitamin content. According to Rodale, however, the user of 'artificial' fertilizers and sprays has caused almost all the nation's health disorders, including cancer".13. Thankfully, the organic food industry has forgotten the more embarrassing claims that it used to make, and concentrates mostly on the issue of pesticides and small-scale farming.
The main problem with organic food is that many of its claims are untrue. It is not healthier than genetically modified foods that are naturally more nutritional, nor are organic foods safer than GM foods that can be grown using fewer pesticides due to inbuilt resistance. It is also the case, rather strangely, that GM foods have been studied so much more than organic foods, and we understand their risks and benefits even better than we do with organic foods. The main source of organic food's success is their marketing which abuses unfounded public fears about GM foods and pesticides.
For a discussion of genetically modified foods (which are massively more common than you might think), see: "The Food Chain: 3.1. Genetically Modified Food" by Vexen Crabtree (2007).
“Several industries have been caught out producing fake and heavily biased science reports, orchestrating so-called "grass-roots" movements whereby they cast doubt on medical science, producing endless reams of misleading public-relations material and manipulating news outlets with fake think-tanks. They have well-practised and efficient methods for manipulating the news and public opinion and the money and effort that goes into these channels of deception are great. They produce "manufactured doubt" using scientific-sounding organisations as fronts, to try and discredit the mountains of evidence that stand against them. They are expert at getting this 'fake news' on to broadcast media and in every success they cause harm, ill health and long-term problems for all.
The worst culprits in spreading mass-lies in this way are: (1) the tobacco and smoke industry15,16,17, (2) the fast-food and junk food industries18, (3) those who sell most nutritional supplements and (4) the petrol and oil industries19,20,15.The worst outlets for promulgating rubbish without checking sources are the sensationalist, downmarket and popularist news bodies.”
You cannot trust much of the news when it comes to issues that have commercial impact, not even when it comes to the reporting of scientific studies on nutrition and food. Some of these studies were funded and managed by scientists supplied by the food industry itself!
“The food industry in Europe recently has been funding groups to protect its position against public and government alarm over obesity, junk food, misleading food labelling, diabetes and the advertising of fatty foods to children. British newspapers routinely carry reports and quotes on diet from the Social Issues Research Center, the British Nutrition Foundation and the International Life Sciences Foundations and routinely fail to point out that all three have received significant funding variously from Cadbury Schweppes, Nestlé, Kelloggs, the Dairy Council, Kraft and the Sugar Bureau. In 2003, Fleet Street reported the comments of a nutritionist called Dr Susan Jebb who attacked the Atkins Diet as 'a massive health risk', without explaining that her research into the low-carbohydrate diet had been funded the Flour Advisory Bureau. This kind of research may or may not be accurate; but it is the hidden hand of PR which is paying for it to happen and promoting it into the news.”
Dr Spector explains how and why pseudoscientific food industries manage to prosper. (1) A main problem is the placebo effect, whereby people think that anything they've tried happens to work. So people who take supplements or adopt a special diet to vitalize themselves feel better simply because they're taking a positive step, even though their actual choice of supplement or diet is meaningless. (2) Another problem is "healthy-person bias": It turns out that health-conscious people tend to volunteer for health and diet science experiments, so, any results tend to show that the people on that particular regime are healthier than average. Such misleading results are easily spun into public-relationships exercises even though reviews by sociological and scientific peers will always pick up on such poor science. Related to this is (3), the fact that the press rarely prints the results of such criticism of studies, and only print the ridiculous initial claims, giving bogus diets exposure and a positive (but unfounded) first-impression. Another vocal critic points out the simple-yet-powerful role of marketing:
“A successful marketing campaign can be scarily effective - make a claim enough times and people will believe it. [... and] link it to a combination of fear and hope, and you can have an entire industry based on nothing but marketing hype. [...] Even when the theory sounds good, we always need to do clinical studies to see what the net effects are in humans.”
Dr Novella (2013)
The late Martin Gardner's first note in his Food Faddists text bemoans the way that reasonable and well-researched science is "drowned out by the louder voices of the charlatans and faddists"2. Dr Spector looks at who gains from the continued reporting21, and I suspect that few readers will find this surprising:
Editors and journals - a high volume of reports maintains sales, interest, advertising, revenue, and so on.
Selected news media - Controversy based on poor medical science increases sales of papers, magazines, and so on.
It seems that it should be easy to outlaw harmful practices and baseless health claims, but, pharmaceutical companies have access to excellent lawyers, and are ninjas at finding legal loopholes. Not only that, but widespread flouting of the law occurs. In 2014 Feb, a round of random tests in the UK found that across 43 vitamin and mineral supplement products, "88% made health claims that are not allowed under legislation because there is no science to support them or were mislabelled as to their content in some way"22.