“Pure, White and Deadly: How Sugar Is Killing Us and What We Can Do To Stop It” is the title of a book written by Professor John Yudkin, who was in the Department of Nutrition at Queen Elizabeth College, London for many years (1). The first edition was published in 1972 and a revised edition appeared in 1986. Professor Yudkin died in 1995 and for many years the book was out of print. However in 2012 Penguin decided to publish it again with an introduction by Robert Lustig, Professor of Pediatrics at the University of California, San Francisco and an ardent campaigner for reducing sugar consumption.
We have now reached a point where there is overwhelming evidence that the official advice to reduce total fat/ saturated fat (SFA) formulated over 30 years was fundamentally flawed. In fact, it is virtually certain this recommendation has been one of the crucial factors contributing to the increased incidence of obesity, Type 2 Diabetes (T2D) and related conditions/diseases. It is arguably the most disastrous policy failures in the field of public health which has ever occurred. The inevitable consequence is that millions of people have suffered and died prematurely.
In order to understand how and why this happened we have to look at the developments in research in the period after the war, when there was a concerted effort, particularly in the USA, to tackle heart disease because it was one of the leading causes of death. It was accepted that the habitual diet was one of the factors involved but 2 different theories emerged. In the USA, Ancel Keys put forward the proposition that excess fat/SFA was a primary cause and therefore the amounts of these constituents in the diet should be reduced. By contrast, John Yudkin argued that the key issue was excessive sugar in the diet. It was of course Keys who prevailed and his views were effectively endorsed by publication of “Dietary Goals for the United States” for the McGovern Committee of Congress in February 1977 (2). An excellent account of the politics and other relevant issues is given by Nina Teicholz in “The Big Fat Surprise” (3).
Once the Americans decided that fat was the key problem, the same approach was adopted by the WHO and so many other countries devised nutrition/public health policies using similar “principles”. It is also meant that anyone who did not follow the party line, including John Yudkin, was effectively marginalised. He must have been extremely frustrated at the time of his death although he has been totally vindicated by the recent developments which I am convinced will inevitably force the politicians to re-shape policies on nutrition and public health.
In the meantime it is fascinating to re-visit “Pure, White and Deadly” to discover what exactly the views and conclusions of John Yudkin about 30 years ago. Here is a selection:
• The view that everything that increases cholesterol in the blood is likely to cause heart disease and vice versa is simplistic and naïve. It has hindered a proper understanding of the disease and its causes, which is why more progress has not been made on prevention. The reality is that there are more extensive disturbances than just a rise in in the blood cholesterol. These a rise in the blood triglycerides, a fall in the HDL cholesterol, changes in the blood glucose similar to those which occur with diabetes, including an increase in the insulin level in the blood. The activity of many enzymes is altered and the behaviour of the blood platelets is changed. As many as 20 different indicators are changed in people with severe atherosclerosis and so it does not make sense to focus specifically on cholesterol, which any case is not a specially reliable indicator of heart disease. All of this has been confirmed by subsequent research and events.
• With reference to the role of fat in heart disease, he notes that few people were not happy about the original work of Ancel Keys which was based on analyses of data which related the amount of fat consumed to the incidence heart disease in 6 different countries to produce a straight line. Although this showed an association it certainly did not confirm cause and effect. However Yudkin commented that the straight line disappeared when data from other countries, were incorporated into the study. More recently Zoe Harcombe has done a detailed critique of the Keys work, which completely destroyed any credibility which still existed (4).
• Epidemiological studies with sugar and heart disease for many countries showed that the there was a closer relationship than with fat. Accepting the limitations of this approach it at least makes the point that the case against sugar is at least as strong as that against fat. In addition the information for Great Britain demonstrated that the rise in sugar consumption preceded very closely the rise in deaths from heart disease. Data from South Africa showed that black population, which consumed little sugar, had a low incidence of heart disease. By contrast, the whites and the Indians who consumed much the same as the British, Americans or Australians, had comparable rates of heart disease. Furthermore, as sugar consumption by the blacks increased there was also an increase in heart disease. A similar picture was observed in Yemenis who moved to Israel. When they arrived, the incidence of heart disease was relatively low but it increase as they adapted to the typical diet in Israel, which has a high sugar content. Coronary disease is common on the island of St Helena where the residents consume less fat than in the USA or Great Britain, are very active because there is little mechanical transport and cigarette smoking is limited. However their consumption of sugar is about 40 kg per year which is high. It is clear that the totality of the epidemiological evidence is undoubtedly consistent with the case that sugar is a prime (but not the only) factor causing heart disease.
• In order to go beyond the study of populations, Yudkin and colleagues decided to investigate the sugar consumption of individuals to see if there was any differences between those with heart disease and those without. In one study, patients who had just suffered their first heart attack were compared with a control group. The sugar intake of the coronary patients was 113 gms per day but in the controls it was 58 gms per day. This study was criticised on the grounds that it had not been blinded (those obtaining the data knew which people had suffered a heart attack). In a second study, blinding was done but the results were essentially similar. The coronary patients were consuming 74 gms per day. This time there were 2 control groups: one had 67 gms and the other 74 gms per day. This type of study had NEVER been done for fat. Once again, the results were consistent! Although Yudkin goes to great pains to emphasise that this evidence does not constitute absolute proof and even if sugar is shown to be a cause of heart disease it will not be the only one.
THE NEXT BLOG CONTINUES WITH MORE FROM JOHN YUDKIN
1. John Yudkin (2012) “Pure, White and Deadly” Penguin London ISBN: 978-0-241-96528-3
3. Nina Teicholz. (2014)“The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet” Simon & Shuster: New York
4. Zoe Harcombe (2010) “The Obesity Epidemic” Columbus