(OMNS Jan 17, 2018) Throughout 2017 I kept saying "This looks like the year that the whole fat-cholesterol-heart disease hypothesis falls apart." Well for once it looks like I was right. Today (I write on Jan 1st 2018) the annual review from Diabetes.co.uk carries 3 game-changing headlines from the past year:
"Saturated fat myth challenged"
"High carb diet 'increases heart risks'"
"Eating low fat could increase early death risk"
Let's look at the history. (Flashback effects, please)
Interior: a scientific laboratory at Oxford University, 1956:
Eccentric British scientist Professor Hugh MacDonald Sinclair is doing something with a test tube. This is a man who lived on a complete Inuit diet (no plants, no land animals) for 3 months and said it was fine, except that because of the anticoagulant effect, "When I prune the roses my boots fill up with blood."
"We were fortunate in having Dr. Ancel Keys recently to work with us and I had been impressed in general with his belief that total dietary fat, of whatever kind, was related to atheroma. Since then I have come to realize that Keys's hypothesis is not correct: what matters in atheroma is, I believe, the amount and structure of the dietary fatty acids".
Sinclair actually wrote that in a letter to the Lancet (1), which was described at the time as a professional suicide note - and so it proved; he lost his job and his laboratory soon after. Mind you, as he later explained, that was exactly 10 years after Oxford University's medical advisers had reported that a generous offer from the recently established Wellcome Trust...to establish a Wellcome Institute of Human Nutrition should be refused because; 'in 10 years' time there will be no human nutritional problems to work on.'
Honestly, do you laugh or cry?
Sinclair described his own theory on lipids simply:
"The causes of death that have increased most in recent years are lung cancer, coronary thrombosis, and leukemia; I believe that in all three groups deficiency of EFA (Essential Fatty Acid) may be important."
Now, six decades later, researchers are finally demonstrating that he was right. What kept them?
Apparently Ancel Keys didn't like the weather in Britain, nor his job of lecturing undergraduates, and he soon escaped to southern Italy, where he later built a villa on the proceeds of a couple of diet books. He continued to develop his theory on fats, and in 1978 first published the now-infamous Seven Countries Study (2). This showed that there was an association between high cholesterol and risk of cardiovascular disease, but made the fundamental error of assuming that association meant causation.
The Seven Countries Study sparked a vigorous debate about "causal inference" and led to the guidelines that in Britain we know as the Bradford-Hill criteria (3), although in the USA they are rightly attributed to the Surgeon General's report on Smoking and Health of 1964 (4), which used them to nail down that smoking-and-cancer causation once and for all.
Too late to catch Ancel out, though - the fat and heart hypothesis caught on and led to 50 years and a multi-billion dollar industry of low-fat food - and to massive increases in obesity, diabetes, heart disease, cancer....
Not to mention statins of course - a $30 billion turnover per annum industry, last time I checked. No wonder Sir Rory Collins of the Cholesterol Treatment Trials (CTT) Collaboration (also at Oxford Uni) has been fighting a rearguard action for years now against, well, anybody who can think, really. He furiously attacked the BMJ (5) for publishing a paper which slightly exaggerated the 17% rate of side-effects in people taking statins into "nearly 20%", and claimed it would cost lives (6). When asked to show the raw data on side effects he said he couldn't because it belonged to the Pharma companies who funded the studies. (The dog ate my homework.)
One of the good guys in this is Uffe Ravnskov in Sweden, who has been challenging and questioning the fat-heart hypothesis for years. He co-authored a great paper in 2015 called How statistical deception created the appearance that statins are safe and effective. (7)
How did they do that? Using one of the oldest fairground statistical tricks in the book - confusing the difference between relative and absolute risk. This paper explains;
"Consider a 5-year trial that includes 2000 healthy, middle-aged men. The aim of the trial is to see if a statin can prevent heart disease. Half of the participants are administered the statin and the other half a placebo. In most clinical trials, we find that during a period of 5 years about 2% of all healthy, middle-aged men experience a nonfatal myocardial infarction (MI). Consequently, at the end of our hypothetical trial, 2% of the placebo-treated men and 1% of the statin-treated men suffered an MI. Statin treatment, therefore, has been of benefit to 1% of the treated participants.
"Thus, the Absolute Risk Reduction, which quantifies how effective a treatment is on the population at risk, was one percentage point. When it comes to presenting the findings of this hypothetical trial...using Relative Risk Reduction the directors can state that statin treatment reduced the incidence of heart disease by 50%, because 1 is 50% of 2."
A better, less fudge-able way of looking at the figures is using NNT - the Number Needed to Treat in order to benefit one person. In this example, you would need to treat 100 men with statins to prevent heart attack in one. Thennt.com is a great website and what it actually says right now about statins (in persons without known heart disease) is (8);
None were helped (life saved)
1 in 104 were helped (preventing heart attack)
1 in 154 were helped (preventing stroke)
1 in 50 were harmed (develop diabetes)
1 in 10 were harmed (muscle damage)
It's not great, is it? How could we all get it so wrong? I blame Ancel Keys (and the weather in Oxford -- though it's not that bad, honestly). And the food and pharmaceutical industries, for whom it's been far from wrong; sell them junk food that makes them fat and ill, then sell them drugs that don't make them much better, and just keep on doing it year after year.
I do blame Ancel Keys, because the other big study he was involved with was the Minnesota Coronary Experiment (1968-73), on which he was co-principal investigator. This actually showed that lowering cholesterol from the study average of 208 mg/dL to 178 mg/dL (US units) or 5.4 mmol/L to 4.6 mmol/L (UK units) will increase your risk of death by 35%. Keys must have known this in 1973, but he/they never published it. It took a re-analysis in 2016 (9) to figure it out.
Meanwhile, back at the 3 headlines;
The first of these news items - Saturated fat myth challenged - reports on an April 25, 2017 editorial (10) in the British Journal of Sports Medicine (no idea why that journal, but it's part of the BMJ group - the same one attacked by Rory Collins so vigorously):
"Saturated fat does not clog the arteries: coronary heart disease is a chronic inflammatory condition, the risk of which can be effectively reduced from healthy lifestyle interventions.
"Despite popular belief among doctors and the public, the conceptual model of dietary saturated fat clogging a pipe is just plain wrong. A landmark systematic review and meta-analysis of observational studies showed no association between saturated fat consumption and (1) all-cause mortality, (2) coronary heart disease (CHD), (3) CHD mortality, (4) ischaemic stroke or (5) type 2 diabetes in healthy adults."
The landmark systematic review referred to is the PURE study (11).
Take-home message? It's in the title; Saturated fat does not clog the arteries. So tell me; did you read about that in the papers or online? It hasn't exactly set the world on fire. I wonder why that is.
I have to add a small qualifier here, or people will challenge me with papers like this one (12) which does show a small decrease in coronary heart disease, with decreasing sat fat intake (18 percent relative risk, which means an absolute risk reduction of 1 in 1000 per person per year). This is true, but it's not as big a story as the harm done by too much carbs.
The second one, High carb diet 'increases heart risks' reports how leading cardiologist and former President of the World Heart Federation Dr Salim Yusuf has publicly stated, in a lecture at a major cardiology conference, that increased intake of carbohydrate is harmful.
"Some fats are good, some fats may be neutral but it is carbohydrate that is the worst thing."
"Absolutely no evidence that low-fat milk is better for you."
"If you look at dairy sources of fat, it is protective. If you look at meat sources of saturated fats, it is neutral and if you look at white meat, this is chicken and fish, there's a trend toward benefit."
The final headline, Eating low fat could increase early death risk, also refers to the mega PURE study (135,000 people, 18 countries, 7 years follow-up). A major report appeared in the Lancet on August 29, 2017 (11): Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study.
The stated conclusion was;
"High carbohydrate intake was associated with higher risk of total mortality, whereas total fat and individual types of fat were related to lower total mortality. Total fat and types of fat were not associated with cardiovascular disease, myocardial infarction, or cardiovascular disease mortality, whereas saturated fat had an inverse association with stroke. Global dietary guidelines should be reconsidered in light of these findings."
So it's not just me, or "lunatic charlatans" like me, saying it: it's official now. Sugar is the Devil, and Fat is our Friend. But remember, Sinclair was right - it's not just that we all eat too much carbs, we also eat too little fat and oil. Way too little. In that Lancet letter he said "there is an enormous increase in permeability of the skin in EFA (Essential Fatty Acid) deficiency" - and capillary, and blood-brain barrier, obviously. We leak essentials out, and toxins in, triggering inflammation that we have leaked the resources to deal with. Eating fat doesn't make you fat -- it is the excess sugar and carbohydrate content in the modern diet, in the absence of adequate doses of nutrients, that causes fat buildup and leads to inflammation, metabolic syndrome, and cardiovascular disease. [13,14]
Seriously, we were built to be oil-fuelled, not carb-burning. We talk about living off the fat of the land, not the sugar.
Was that really Santa Claus in the red outfit? Could it have been something from the Dark Side?
(Dr. Damien Downing, who is almost certainly not from the Dark Side, practices nutritional and environmental medicine. He was co-founder of the British Society for Nutritional Medicine, and is the current president of the British Society for Ecological Medicine. Dr. Downing is author of The Vitamin Cure for Allergies and coauthor of The Vitamin Cure for Digestive Problems.)