[2017] Lore of Nutrition: Challenging Conventional Dietary Beliefs
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All the dietitians quoted in the Times article said that people who tried the LCHF diet ‘all lost weight extremely fast but as soon as they start eating carbohydrates, they put on even more weight’. Hume went so far as to quote actress Jennifer Aniston, who famously said ‘the carbs will find you’. Without realising it, these dietitians broke the omertà – the code of silence never to acknowledge that carbohydrates cause corpulence. In trying to argue that the LCHF eating plan causes weight gain, they inadvertently admitted that carbohydrates cause obesity.
By some convoluted (il)logic, their argument – that the moment you stop eating LCHF (which successfully produces weight loss) and reintroduce carbohydrates, you regain all the lost weight, and then some – is meant to cast the LCHF diet as the cause of weight gain, not the reintroduced carbohydrates. But what we should actually deduce is that, to avoid weight gain, humans should limit the amount of carbohydrates they eat (for life), exactly as the LCHF eating plan advocates.
On 9 October 2012, shortly after the publication of Dr Martinique Stilwell’s article in the Mail & Guardian (see Chapter 3), the HPCSA issued a statement, quoting Professor Edelweiss Wentzel-Viljoen, then chairperson of the HPCSA Professional Board for Dietetics and Nutrition, who would later play a crucial supporting role in launching the HPCSA case against me (see Closure):
‘Although low-carbohydrate diets containing less energy may have short-term beneficial effects on weight control and insulin resistance in some individuals, a healthy diet remains a balanced diet … Exercise plays a very important role in reaching and maintaining a healthy weight. A healthy diet remains one that is balanced in terms of carbohydrates, protein and fats as well as vitamins and minerals. The best way to reach a healthy balanced way of eating is to follow the South African Food Based Dietary Guidelines,’ Prof Wentzel-Viljoen explains.41
The statement also warned that high-protein, high-fat and low-carbohydrate diets ‘have severe health consequences for those who follow them long term’, and expressed concern about controversial and unhealthy diets ‘being recommended by individuals who are not specialised in dietetics and nutrition’.
Of course, one of the dangers of talking about health and weight is that your own body shape reveals much about whether what you practise actually works. Chris Becker, an LCHF supporter, decided to investigate how well their own dietary advice was helping the senior HPCSA administrators control their weight. His conclusion, based on a comparison of photographs of me with those of senior HPCSA administrators, was that my dietary advice seemed to be working better for me than the HPCSA’s advice was working for its employees. ‘If these high-level government employees of the HPCSA are following their own, i.e. government dietary guidelines, well, then I don’t need to say any more. Neither does Tim Noakes,’ wrote Becker.42
The HPCSA statement introduced the concept of the ‘healthy’ ‘balanced’ diet without defining exactly what is meant by ‘balanced’. I find it difficult to understand how a diet can be balanced if more than 50 per cent of its energy comes from a single nutrient – carbohydrate – for which the human body has no (i.e. zero) essential requirement. Surely a ‘balanced’ diet should contain, for example, one-third fat, one-third carbohydrate and one-third protein? And if not, why not?
The statement contained two other warnings that would become the rallying call for all those queuing up to attack me. The first, that the LCHF eating plan may have ‘severe health consequences’ in the long term is ironic coming from a former professor of dietetics and nutrition at Stellenbosch University, one of the three major universities in the Western Cape, under whose watch that province has become the T2DM capital of South Africa. Should Wentzel-Viljoen not be asking herself if there is even the tiniest possibility that the South African Food-based Dietary Guidelines, promoted by both the HPCSA and ADSA, could be the real cause of this problem?
The second is the board’s implication that I am not qualified to give any dietary opinions, as I am ‘not specialised in dietetics and nutrition’. Interestingly, when I had many fewer qualifications and was promoting the South African Food-based Dietary Guidelines throughout the country and to the rest of the world through my book, Lore of Running, not a single South African dietitian or professional board paid the slightest attention to what I was saying. It would appear that it is not my qualifications that are the problem; rather, it is what I am now saying publicly that has become the problem.
The timing of this statement is important, because it shows that already in October 2012 the HPCSA was taking an interest in my professional activities in nutrition, and that Wentzel-Viljoen was raising the initial ‘concerns’ from her position as chairperson of the most powerful and influential dietetics committee in the country.
Four months later, in February 2013, Dr Vash Mungal-Singh wrote an open letter to the press in her capacity as CEO of the HSFSA to express her opinion that my ideas were wrong and, indeed, dangerous. The letter began with the conventional statement that any diet, be it low fat or high fat, will cause weight loss provided it is calorie-restricted. ‘Yet we know many people revert to their old eating habits,’ Mungal-Singh wrote, ‘and regain the lost weight, plus more.’43 It was unclear what scientific point she was trying to make here, since the dietary advice I give is that unless one is prepared to continue with the LCHF eating plan for life, it is better not to start in the first place. This is something I have stated repeatedly.
The letter continued:
The HSF does not say ‘no’ to fats! But the message is more nuanced. For good health we need some fat in our diet. The real issue is the quality of fats we eat, against the total kilojoules in the diet. While studies are unclear about the effect of saturated fats on health, there is solid proof that replacing saturated fats with unsaturated fats will improve cholesterol levels, reduce heart disease risk and prevent insulin resistance, a precursor of diabetes. Eating good fats in place of saturated fats lowers the risk of heart disease. Replacement is key.’
Mungal-Singh conveniently forgets to mention that the HSFSA has major conflicts of interest: it accepts funding from three companies that produce highly processed seed oils containing unhealthy omega-6 polyunsaturated fats and, until very recently, even more unhealthy trans fats (see Table 7.1). Among this group is Unilever, the world’s largest producer of polyunsaturated ‘vegetable’ oils and, coincidentally, ice cream.
Table 7.1 HSFSA sponsors
Producers of polyunsaturated fats/margarine
Platinum sponsor
Willowton Group (Sunfoil Sunflower Oil, Sunshine D Margarine, Wooden Spoon Margarine)
Gold sponsor
Unilever (Blue Brand Margarine, Flora, I Can’t Believe It’s Not Butter, Stork)
Sponsors and partners
Unity Foods (Helios Sunflower Oil, Helios Margarine, Ruby Margarine, Golden Lite)
Producers of confectionery
Gold sponsor
Tiger Brands (Allsorts, Anytime, Beacon chocolates, Black Cat snacks, Fizzer, FizzPop, Jelly Tots, Jungle Oats Energy Bars, Maynards, Beacon mmmMallows, Smoothies, Sparkles, Toff-o-Luxe, Beacon Easter eggs)
Producers of breakfast cereals/grain products
Gold sponsor
Tiger Brands (Ace, Ace Instant Porridge, Albany, Aunt Caroline, Cresta Rice, Fattis and Monis, Golden Cloud, Jungle Oats, King Korn, Morvite, Simply Cereal)
Unilever (Pot Noodle)
Producers of sugar-sweetened beverages
Gold sponsor
Tiger Brands (Energade Sports Drink, Oros, Halls, Roses)
Producers of ice cream
Gold sponsor
Unilever (Algida, Ben & Jerry’s, Carte d’Or, Cornetto, Magnum, Ola, Viennetta, Wall’s)
Academic/research institutions
Sponsors and partners
Cape Peninsula University of Technology
Medical Research Council
North West University
Stellenbosch University
Faculty of Health and Med
ical Sciences
University of Cape Town
Chronic Disease Initiative for Africa
Communication and Marketing Department
Division of Human Nutrition
Hatter Institute of Cardiology Research
Sports Science Institute of South Africa
Other government institutions
Sponsors and partners
Western Cape Department of Health
The list of HSFSA sponsors and the products they produce explains why the concept of eating real foods and avoiding cereal- and sugar-based products is so challenging to the HSFSA, as it is to all such organisations around the world. Nowhere is this conflict more apparent than in the HSFSA’s Heart Mark programme. According to the current CEO of the HSFSA, Professor Pamela Naidoo: ‘Reading food labels and lists of ingredients requires time and advanced knowledge in nutrition, which many consumers don’t have. The Heart Mark offers the consumer a tool to make choosing healthier foods easier.’44
In other words, the public is not intelligent enough to understand that processed foods should not be eaten. So the HSFSA will ‘health-wash’ some of the very worst foods by calling them healthy and therefore save the ignorant consumer from ever realising just how unhealthy they are. In this way the HSFSA can health-wash a range of sugar-loaded, highly addictive products that are the direct cause of South Africa’s obesity epidemic.
The effect of this industrial capture of health organisations is nowhere better demonstrated than in their slow reaction to research into the harmful effects of trans fats. Dr Mary Enig established in the 1970s already that trans fats produced by the chemical extraction of unstable polyunsaturated oils from seeds are unhealthy, yet only recently have heart foundations begun to acknowledge this fact.45 And not one heart foundation anywhere has ever acknowledged their role in the promotion of this unhealthy foodstuff. Rather, it is as if their 40-year advocacy of so-called healthy polyunsaturated ‘vegetable’ oils containing trans fats simply never happened.
The reaction to Enig’s discovery was predictable. As described in her book, no sooner had her first paper been published than representatives of the National Association of Margarine Manufacturers and the Institute for Shortening and Edible Oils came to visit her, warning her that unless she ceased her research, she would lose all her funding. Which is exactly what happened: ‘The lipid group at the University of Maryland never got another penny for trans fat research, and as the professors retired, the group’s effort was gradually abandoned.’46 As a result, Enig’s finding of a correlation between vegetable-fat consumption, trans-fat consumption and serious disease, including heart disease, was simply ignored and buried, as ‘no one was doing [the research]’. Enig’s career, like that of Professor John Yudkin, who tried to warn the world about sugar, was terminated as a result of industry’s need to put profits before the health of people.
Getting back to Mungal-Singh, what is the evidence that unsaturated fats ‘will improve cholesterol levels, reduce heart disease risk and prevent insulin resistance’? The first point is that even if polyunsaturated fats lower blood cholesterol concentrations, so what? We want to know whether or not replacing saturated fats with polyunsaturated fats allows us to live longer, healthier lives. Here, the balance of evidence from a series of RCTs is absolutely clear: there is no evidence that replacing saturated fats with polyunsaturated fats improves health outcomes. Let’s consider two such studies.
Ancel Keys’s diet-heart hypothesis predicts that saturated fats raise blood cholesterol concentrations, which then clog the coronary arteries, causing heart attacks. One way to test this hypothesis is to replace dietary saturated fats (from animal fats, common margarines and shortening) with omega-6 linoleic acid from either safflower oil and safflower-oil polyunsaturated margarine, or from corn oil and corn-oil polyunsaturated margarine. Two studies evaluated these two interventions: the Sydney Diet Heart Study (1966–1973) and the Minnesota Coronary Experiment (1968–1973), the latter directed by Keys himself.
For a variety of reasons, the data for both studies was not fully reported until Dr Christopher Ramsden and his colleagues from the NIH in Bethesda, USA, were able to recover the original data and subject it to an exhaustive, modern analysis. The findings of both studies were essentially identical. In their investigation into the Sydney Diet Heart Study, Ramsden et al. found that:
In this cohort, substituting dietary linoleic acid in place of saturated fats increased the rates of death from all causes, coronary heart disease, and cardiovascular disease. An updated meta-analysis of linoleic acid intervention trials showed no evidence of cardiovascular benefit. These findings could have important implications for worldwide dietary advice to substitute omega 6 linoleic acid, or polyunsaturated fats in general, for saturated fats.47
In other words, there is no evidence that replacing saturated fats with polyunsaturated fats improves health.
Similarly, Ramsden’s modern analysis of Keys’s Minnesota Coronary Experiment found that: ‘There was no evidence of benefit in the intervention group [those eating a diet where saturated fat was replaced with linoleic acid] for coronary atherosclerosis or myocardial infarcts.’ In fact, they found ‘a 22% higher risk of death for each 30 mg/dl (0.78 mmol/L) reduction in serum cholesterol’. This effect was especially apparent in those over 65 years old, so that after about 400 days on the diet, the cumulative number of deaths for those ingesting linoleic acid in place of saturated fat became progressively greater than for those who continued to eat saturated fats. ‘In meta-analyses, these cholesterol lowering interventions showed no evidence of benefit on mortality from coronary heart disease … or all cause mortality,’ concluded Ramsden and his colleagues.48
There are other studies that support this interpretation. In fact, the very first study of vegetable-oil substitution for saturated fat was published in 1965. G.A. Rose and colleagues showed that whereas corn oil lowered the blood cholesterol concentrations of patients with heart disease, the proportion of heart patients who were still alive after two years was significantly less (52 per cent) in the group fed corn oil than in the group who continued to eat as they always had (75 per cent). The authors concluded that ‘under the circumstances of this trial corn oil cannot be recommended in the treatment of ischaemic heart disease’.49
Another study conveniently hidden from view is the Helsinki Businessmen Study.50 In that study, mortality was much higher in the intervention group, which was treated with medications to lower blood cholesterol concentrations and blood pressure, as well as ‘intensive dietetic-hygienic measures’ that would have included substituting saturated fats with vegetable oils. Predictably, the authors once more ignored the null hypothesis, concluding: ‘These unexpected results may not question multifactorial prevention as such but do support the need for [more] research’. Interestingly, the blood glucose concentration taken one hour after glucose ingestion was the best predictor for mortality in the intervention group. This is compatible with the theory that IR is the real determinant of ill health. Could the findings also have been the result of the prescription of a higher-carbohydrate diet in the intervention group, as occurred in Rossouw’s CORIS trial (see Chapter 4)?
In 2004, Dr Dariush Mozaffarian, a lifelong proponent of the health benefits of substituting polyunsaturated fats for dietary saturated fats,51 who sits on the scientific advisory board of Unilever, the world’s largest producer of polyunsaturated fats, completed a novel study of changes in coronary arterial narrowing due to atherosclerosis in 235 post-menopausal women in relation to what the women reported they ate. Inconveniently, the study found that ‘a greater saturated fat intake is associated with less progression of coronary atherosclerosis, whereas carbohydrate intake is associated with greater progression’. Remarkably, in the text but not in the abstract, Mozaffarian and his colleagues were prepared to admit (as was clearly shown in the data) that both ‘polyunsaturated fat and carbohydrate intakes were associated with greater progression’.52
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p; As cardiovascular research scientist James DiNicolantonio and his colleagues assert, the totality of evidence shows that there is no definitive proof that replacing saturated fat in the diet with polyunsaturated fats will reduce the risk of heart attack or extend life.53 Remarkably, a new meta-analysis concludes that: ‘Due to null results and a small number of studies included there is no strong evidence that replacement of saturated fatty acids with unsaturated fatty acids may benefit lipid profiles in this population [my emphasis].’54
Interestingly, there are other scientific findings relating to the ingestion of polyunsaturated fats or ‘vegetable oils’ that are conveniently forgotten. Thus the ingestion of omega-6 rich linoleic acid in vegetable oil increased blood triglyceride concentrations in people with elevated blood triglyceride concentrations, whereas fish oils had the opposite effect.55 Yet I have still to read the HSFSA warning those with hypertriglyceridaemia not to ingest vegetable oils, or to advise them that the LCHF diet reverses hypertriglyceridaemia.
Another study found that replacing saturated fat with an increased intake of polyunsaturated fat in vegetables increased blood concentrations of oxidised LDL-cholesterol and lipoprotein(a).56 These are changes that would normally be considered as evidence for an increased risk for the future development of CHD, the opposite of what the HSFSA claims should happen when one replaces saturated fat with polyunsaturated fats in vegetable oils.
The HSFSA does not warn us that replacing saturated fat with refined carbohydrates, which is precisely what has happened in the US since the publication of the 1977 US Dietary Guidelines for Americans (Figure 17.9), adversely affects insulin secretion.57 The HSFSA also never tells us of the potential benefits of exchanging carbohydrate in the diet for saturated fat. A recent study found that replacement of dietary saturated fat with monounsaturated fats or refined carbohydrates did not improve ‘inflammatory and thrombogenic markers in abdominally overweight individuals’.58 Instead, ‘increased refined carbohydrates consumption adversely impacts fasting HDL subfractions’.