[2017] Lore of Nutrition: Challenging Conventional Dietary Beliefs
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Cleave and Campbell next presented evidence that T2DM is more common in countries that eat more sugar. Like Weston Price, they argued that the rising incidence of T2DM in American Indians, the Inuit, the Icelanders, the ‘Black Jews’ who moved to Israel from Yemen, and the Pacific Islanders coincided with the adoption of the high-sugar Western diet. Interestingly, Cleave and Campbell understood that ‘obesity is not due to diabetes, nor diabetes to obesity, but both arise from a common cause’.101
The work of Professor John Yudkin
The final nutrition scientist who has until very recently been written out of history is John Yudkin, formerly professor of nutrition and dietetics at the University of London from 1954 to 1971. Yudkin’s error was to provide answers to the question he posed in the introduction to his classic book Pure, White and Deadly: ‘I am often asked why we don’t hear very much about the dangers of sugar, while we are constantly being told we have too much fat in our diet and not enough fibre. I suggest that you will find at least part of the answer in the last chapter of this book.’102 Perhaps unwisely, he concluded the opening chapter of his book with the statement: ‘I hope that when you have read this book, I shall have convinced you that sugar is really dangerous. At the very least, I hope I shall have persuaded you that it might be dangerous … If as a result you now give up all or most of your sugar eating … I shall not have wasted my time in writing the book, and more importantly you will not have wasted your time in reading it.’103
Yudkin’s thesis is essentially the same as that of Cleave and Campbell, specifically:
The diet of early man contained little carbohydrate. With the discovery of agriculture, the amount of carbohydrate increased, and the amounts of protein and fat decreased … Increasing prosperity, both between countries and within a country, leads to an increasing proportion of sugar being bought in manufactured foods, rather than as household sugar. It is suggested that the effect of this is that wealthier countries, and the wealthier section of a national population, tend to have a higher intake of calories from the accompanying flour, chocolate, fat and other ingredients of these manufactured foods … one of the effects of this contribution of calories from sugar-containing foods is to reduce the consumption of nutritionally desirable foods, such as fruit and meat … In the wealthier countries, there is evidence that sugar and sugar-containing foods contribute to several diseases, including obesity, dental caries, diabetes mellitus and myocardial infarction … the known association of the prevalence of diabetes and of myocardial infarction with the level of fat intake is fortuitous and secondary. It is more likely that the primary association is with levels of sugar intake, which I have shown are, in turn, closely related to levels of fat intake.104
For suggesting this hypothesis and for devoting the latter part of his scientific career to the study of the medical consequences of ingesting sugar, Yudkin was demonised and ultimately excommunicated from the research community, losing all his research funding. He was pretty certain who was behind it:
It is difficult to avoid the conclusion that this is the result of the vigorous, continuing and expanding activities of the sugar industry. Their product is pure and white; it would be difficult to use these adjectives for the behavior of the product and distributors and their intermediates … The result is such a compact nucleus of power that, like a magnet surrounded by a strong induction coil, it produces a field of influence that invisibly affects many of those not in direct contact with the centre.105
In 2009, paediatric endocrinologist Robert Lustig released a YouTube video titled Sugar: The Bitter Truth, in which he highlighted the (now) established dangers of sugar and high-fructose corn syrup.106 The video has been viewed more than seven million times to date. In 2013, Lustig published Fat Chance: Beating the Odds Against Sugar, Processed Food, Obesity and Disease, in which he fully vindicated Yudkin.107 Three years later, Gary Taubes would do the same in The Case Against Sugar.108 In 2012, on the 40th anniversary of its first publication, Yudkin’s Pure, White and Deadly was re-published with a foreword by Lustig.
Another significant modern contributor to this science is Professor Richard J. Johnson, now of the Department of Medicine at the University of Colorado, Denver. Johnson was interested in discovering the metabolic ‘switch’ that hibernating animals, such as bears and squirrels, use to gain weight by storing fat in the autumn prior to hibernation. He discovered that the key lies in the production of uric acid by an enzyme called AMP deaminase, which is present in all cells, but is of particular importance in the liver.109 He then found that fructose activates this enzyme.
Thus, Johnson’s theory is that the fructose in sugar increases uric acid production, which switches susceptible humans into hibernation mode, producing hyperphagia (overeating due to increased hunger), IR, and elevated blood glucose, insulin and triglyceride concentrations, leading to fat accumulation in the liver and fat cells. He believes that it is the increase in sugar consumption over the past 50 to 100 years that is the single most important driver of the IR/metabolic syndrome/obesity/T2DM epidemics.
The case against sugar, begun by Cleave, Campbell and Yudkin, has now become mainstream.
Summary
It seems to me that in this series of books and articles that are never discussed or presented to modern medical students, a group of highly inquisitive scientists have clearly established that humans are not designed to be unhealthy. Instead, we are the survivors of a biological arms race that we entered four to six million years ago when our puny and highly vulnerable hominin ancestors left the safety of the jungles and forests to become savannah dwellers – they survived by eating the fat of other animals specifically to fuel our enlarging, metabolically expensive brains.110 As a result, humans have a strong preference for high-fat foods, including the capacity to determine the fat content and food reward of different foods within milliseconds.111
Over the course of the next four million years, we became remarkably robust and healthy. Only when we began to eat cereals at the start of the agricultural revolution, and most especially when our ancestral food choices were displaced by the ‘displacing foods of modern commerce’, did the ‘modern diseases of lifestyle’ begin to emerge in ever-increasing numbers.112
The key point is that these diseases are not ‘of lifestyle’. Rather, they are caused by the ‘displacing foods’ that industry wishes us to eat.
In the next chapter, I explain how this degrading of human health was accelerated largely by the efforts of one man, Dr Ancel Keys, who, ignoring the work of McCarrison, Price, Cleave, Campbell and Yudkin, plunged the world into the worst health crisis in history. Keys was the father of what will be judged, in time, as the greatest mistake in modern medicine/science: the acceptance of the diet-heart and lipid hypotheses without adequate evidence.
*Much of the research of obesity and diabetes in Native Americans has focused on the Pima Indians, who were subsistence farmers with a higher-carbohydrate intake. Pima obesity began when their water supply was cut off with the building of the Hoover Dam in Colorado and they were no longer able to farm. As a result, the conclusion has been drawn that Native Americans became obese when they began to eat a higher-fat diet, conveniently exonerating the 1977 US dietary guidelines of any blame. But the opposite has occurred in the Plains Indians, whose obesity is clearly associated with the adoption of the modern industrial diet, which contains less fat and protein than their historic carnivorous diet of bison. For some reason, the cause of obesity in the Plains Indians is almost never discussed or researched. This raises many questions.
17
The Worst Mistake in the History of Medicine
‘But biology does not readjust to accommodate the false theories of scientists …’
– James le Fanu, British physician1
The agricultural revolution initiated Homo sapiens’ ruinous move away from carnivory to diets dominated by cereals, grains, vegetable oils and sugar. But it was the second great dietary disaster, the adoption of the 19
77 Dietary Guidelines for Americans, that initiated the devastating obesity/T2DM epidemic that has swept across the globe since the 1980s.
The US dietary guidelines were the first ever to inform the general public about what should not be eaten. Specifically, we were told to avoid fat, especially saturated fat, and to replace dietary saturated fats with carbohydrates and polyunsaturated ‘vegetable’ (actually seed) oils. Failure to do so, we were warned, would cause us all to die of heart attacks, because cholesterol, we were told, causes coronary heart disease. Instead, the advice drove us down the road to obesity and the much more severe form of arterial disease caused by T2DM.
Some have described this monumental error as the greatest scam in the history of modern medicine. The fallout has produced some very big ‘winners’, specifically those pharmaceutical companies that have benefited from the sale of the largely ineffective statin drugs, and the processed-food industry, dominated by 10 companies that produce the ‘displacing foods of modern commerce’ (see Figure 17.1 on page 338).
So how did this all come about?
In 1955, US president Dwight D. Eisenhower suffered a heart attack while in office. This event focused national attention on an apparently dramatically rising rate of heart attacks in the US. On the advice of his attending cardiologist, Dr Paul Dudley White, during his illness Eisenhower received dietary advice from Dr Ancel Keys, a biologist at the University of Minnesota. Although Keys was still in the process of developing a model to explain how specific foods cause heart disease, he was sufficiently certain to prescribe the completely unproven low-fat diet to the most powerful politician in the world. Unfortunately, Keys’s untested diet was largely ineffective, possibly even harmful.
Figure 17.1
The 10 companies that control almost every large food and beverage brand in the world
On the low-fat diet, Eisenhower complained that he was always hungry; his blood cholesterol concentration rose progressively; he became increasingly irritable; and he suffered a further six heart attacks before dying from heart disease at age 78 in 1969.2 Not a great advert for Keys’s dietary approach.
At the time, there were essentially three competing possibilities to explain the rising incidence of heart disease: saturated fat intake; cigarette-smoking, which was Eisenhower’s vice and which had increased dramatically during and after the First World War (see Figure 4.1 on page 64); and sugar, the global consumption of which took off at about the same time (Figure 17.2 on the following page). A fourth possibility – an increased intake of trans fats produced in the production of margarines, hydrogenated vegetable oils and shortening – would only be revealed some years later, largely because of the persistence of two pioneers: Dr Mary Enig3 and Dr Fred Kummerow.4
Whereas cigarette-smoking and sugar intake had clearly increased steeply to match the increase in heart disease, at that time there was no data showing changes in saturated fat intake in the US over the same period. Even today, this information is difficult to find.
Figure 17.2
The change in sugar intake in the UK from 1700 to 1978, and in the US from 1975 to 2000 (upper line). The change in obesity rates in non-Hispanic white males aged 60–69 is also shown (lower line). Redrawn from R.J. Johnson et al., ‘Potential role of sugar (fructose) in the epidemic of hypertension, obesity and the metabolic syndrome, diabetes, kidney disease, and cardiovascular disease’5
What we do know is that consumption of the three main sources of saturated fat in the US diet – red meat, full-cream milk and all dairy produce (including cheese) – either did not change much (red meat) or fell steeply (milk and consequently all dairy produce, by 15 per cent).6 The result is that saturated fat intake in the US appears to have fallen since 1935, with the greatest fall since 1967.7
In contrast, Enig et al. estimate that the intake of trans fatty acids in the US diet increased almost threefold, from 4.4 grams per day in 1910 to 12.1 grams per day in 1972, comprising 8 per cent of the total daily fat intake. The main contributors to trans fatty acid consumption in 1972 were commercial vegetable oils containing 17 per cent of fat as trans fats, margarines containing 47 per cent as trans fats, and vegetable shortening containing up to 58 per cent as trans fats.8
Today, few would argue that of the four, cigarette-smoking is the most likely leading culprit, with trans fatty acids a close second. Figure 4.1 on page 64 shows a remarkably good fit for an (associational) relationship between the rise and fall of cigarette consumption and the rise and subsequent fall of US heart-disease rates. However, the rise and fall of trans fatty acid consumption follows a similar pattern, because, after 1968, the Institute of Shortening and Edible Oils, responding to the suggestion of Fred Kummerow,9 began to increase the essential fatty acid content of margarine and shortening and to lower the trans fat content of these products.10 As we know, heart-disease death rates began to fall quite dramatically after 1968 (Figure 4.1).
Figure 17.3
Left panel: change in total meat, red meat, poultry and fish consumption in the US from 1909 to 2007. Note that red meat consumption is the same in 2007 as it was in 1909, but has fallen progressively since 1965, whereas the consumption of poultry increased substantially during the same period. Redrawn from C.R. Daniel et al., ‘Trends in meat consumption in the USA’.11 Right panel: change in total, whole-milk and lower-fat milk intakes in the US between 1930 and 2010. Source: USDA, Economic Research Service, Food Availability Data, redrawn from USDA Agriculture Fact Book 2001–200212
But Keys ignored these known relationships, as well as the fact that sugar consumption had also risen during the same period. Instead, he stuck with his personal theory that it was an increased intake of saturated fats from animals that was causing the heart-disease ‘epidemic’. This allowed him to ignore any potential role of polyunsaturated ‘vegetable’ oils, margarine and shortening with their high contents of trans fatty acids, the intakes of which had exponentially increased, or were about to, thanks to the promotion of his theory by, among others, the American Heart Association. We now understand that it was the chemical extraction of polyunsaturated ‘vegetable’ oils from cotton, soy, sunflower and safflower seeds that produced trans fats, which increased the risk of heart disease and perhaps cancer, as argued earlier and in Chapter 7.
Furthermore, Keys ignored the finding that there was a very close relationship between the intake of fat and sugar in most countries, making it impossible to differentiate between sugar and saturated fat as the cause of heart disease.
In 1970, Keys wrote a memorandum that was later published in the journal Atherosclerosis. In it he criticised the theory that sugar is the main dietary factor causing heart disease.13 According to Yudkin, Keys ended his memorandum ‘triumphantly pointing out that both sugar and fat intakes are related to heart disease, but that the cause must be fat, not sugar, because he had found in 1970 that fat intake and sugar intake are themselves closely linked’.14 It was a relationship that Yudkin himself had already shown in 1964.15
Figure 17.4
Left panel: changes in US consumption of butter, shortening, lard, margarine and beef tallow from 1909 to 1999. Note that consumption of butter and lard fell steeply, whereas intakes of shortening and margarine increased dramatically beginning in the 1940s. Right panel: changes in US consumption of ‘vegetable’ oils from 1909 to 1999. Note that the promotion of the diet-heart hypothesis by the AHA produced an astronomical increase in soybean consumption beginning after 1961. Redrawn from T.L Blasbalg et al., ‘Changes in consumption of omega-3 and omega-6 fatty acids in the United States during the 20th century’16
Keys devoted the rest of his life to convincing the world of his diet-lipid-heart hypotheses – that a diet high in fat, especially saturated fat, raises blood cholesterol concentrations, clogging arteries and causing heart attacks and strokes. He also taught the world to fear fat, giving rise to the chronic lipophobia that still exists today.
As described fully in The Real Meal Revolution, Keys performed two associational
studies to show a relationship between the total amount of fat consumed by the citizens of first six17 and then seven countries18 and their rates of heart disease. He showed that the more fat eaten in a particular country, the higher that country’s death rate from ‘degenerative heart disease’.
The problem with such research is that it attempts to identify causative factors on the basis of associational studies. This is pseudo-science. Associational studies can only ever develop hypotheses, which must then be tested using RCTs in which the single factor of interest – in this case total fat or saturated fat intake – is manipulated and the health outcomes monitored in a large number of humans for at least eight years, as was done in the WHI trial (see Chapter 4).
When comparing populations in different countries, the most obvious problem is that they do not differ solely in what they eat. To suggest that differences in heart-attack rates between citizens in the US and Japan can be explained solely on the grounds that the former eat more saturated fat is patently absurd. It ignores a host of other ways in which the citizens of the US and Japan differ. Only those who have already convinced themselves that diet alone determines heart-attack rates would ever fall for such trickery. For more than 60 years – perhaps until the publication of Nina Teicholz’s book The Big Fat Surprise in 2014 – Keys successfully hoodwinked the world into sharing his deception.