One of things I try and do on this blog is right what I see as nutritional wrongs. So, if there’s a common perception that artificial sweeteners are better than sugar for weight loss, but there’s really no evidence for that, then I’m inclined to write about it. If the evidence suggests that margarine is likely to be unhealthier than butter, I’ll write about that too. Similarly, I’ve been keen to point out that it appears that saturated fat, widely taken as to be artery-clogging and heart disease-provoking, is nothing of the sort.
I have written more than once about this, most recently here. This review of the literature found no evidence that saturated fat causes heart disease. And it’s a shame (in my opinion, anyway), that this study got no mainstream publicity.
The same, appears to be true, of a recent report published in the Annals of Nutrition and Metabolism [1]. You can read a complete version of this report here. The whole edition of this journal was dedicated to reporting an ‘Expert Consultation’ held jointly by the World Health Organization (WHO) and Food and Agriculture Organization (FAO) of the US. The consultation took a wide, sweeping look at the relationship between fats, physiology and health, and took place in late 2008. One of the things that was inevitably a focus of the consultation was the link between saturated fat and heart disease.
The ‘experts’ responsible for assessing this relationship looked at two lines of evidence: epidemiological studies and intervention studies. Let’s look at both in turn.
Epidemiological studies look at the relationship between factors (such as smoking and lung cancer, exercise and dementia, saturated fat and heart disease) in populations. These studies can only really tell us about associations between things, but can’t generally be used to inform us if one thing is causing another. Nevertheless, if saturated fat does truly cause heart disease (like we’ve been told for the last few decades), then the epidemiological evidence should show that higher levels of saturated fat are associated with a higher risk of heart disease (also known as ‘coronary heart disease’ or ‘CHD’ for short).
Well, according to the WHO/FAO report, there is no association. Here’s what the report states:
“Intake of SFA [saturated fatty acids] was not significantly associated with CHD mortality…
and also
SFA intake was not significantly associated CHD events [e.g. heart attacks]…”
And now on to intervention studies�
In such studies, individuals a subjected to some sort of intervention (such as a medication, increased exercise or dietary change). The relevant intervention in this area is to put people on a low saturated fat diet diet, and see how they fare compared to individuals who are not subjected to this change. Unlike epidemiological studies, intervention studies can prove ‘causal’ links between things. For example, if eating less saturated fat leads to a reduced risk of heart disease, then it’s a pretty good bet that saturated fat causes heart disease (all other things being equal).
So, what did the WHO/FAO report find with regard to relevant intervention studies? Here’s what:
“…fatal CHD was not reduced by…the low-fat diets…”
Just this week saw the publication of another huge study which assessed the relationship between saturated fat and heart disease [2]. This study was actually an amalgamation (meta-analysis) of 21 epidemiological studies. Taken all together, this review monitored almost 350,000 people over between 5 and 23 years. And here’s what it found:
1. No association between saturated fat and risk of heart disease
2. No association between saturated fat and risk of stroke
You know what this all means, don’t you? That there really is no evidence that saturated fat causes heart disease or cardiovascular disease generally.
Despite all this evidence to the contrary, I suspect the idea that saturated fat causes heart disease will perpetuate for some time. One reason for this has to do with cholesterol. There is some evidence that saturated fat puts cholesterol levels up, and we all know that cholesterol causes heart disease, right? So, if saturated fat puts cholesterol up, it must increased the risk of heart disease too. Well, this line of argument assumes that cholesterol causes heart disease, and actually the evidence shows this is far from assured. But even if it did, the logic is still faulty. We could use the same logic to claim that if something causes cholesterol to fall it must be good for heart health. So, if arsenic and cyanide reduce cholesterol, should we all be swigging these poisons down every day?
Anyway, while the ‘cholesterol causes heart disease’ paradigm is prevalent, I think saturated fat is going to be in the firing line. Shame, because at worst it appears an innocent bystander.
Another reason that saturated fat is likely to get a hard time for some time yet has to do with the fact that paradigms do tend to change very slowly. And at least some of this has to do with a reluctance some of us have to changing our minds about things we ‘know’. Some of us feel we ‘know’ saturated fat causes heart disease, because we’ve been told it so often and consistently we’re not even inclined to challenge this notion. And if we happen to be health professionals or academics who, at least in part, define ourselves by our ‘knowledge’ and ‘intelligence’, it can be mightily difficult to admit that we were wrong.
Not being a literary type, I’m not really a quote person either. But I do know at least one. It is British economist’s John Maynard Keynes’ assertion that When the facts change, I change my mind. What do you do, sir?� How I would like to see health professionals and Government departments take a leaf out of Keynes’ book, and make pronouncements regarding saturated fat and other dietary factors based on science fact (not fiction).
References:
1. Fats and Fatty Acids in Human Nutrition. Annals of Nutrition and Metabolism, 2009; 55 (1-3).
2. Siri-Tarino PW, et al. Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease Am J Clin Nutr 13 January 2010 [epub ahead of print].
The WHO/FAO is not a single report. Instead it is a set of papers, some of which state that saturated fat does not cause heart disease whereas there are other places such as the Introduction article that say things such as “In
contrast, the high intake of saturated fatty acids, and to
an even greater extent trans fatty acids, substantially contributes
to the development of cardiovascular diseases.”
While I am a fan of this blog, perhaps the title of this posting is not totally justified — at least in regard to the WHO/FAO report.
My mother had a series of heart attacks which left her incapacitated.
She was given statins and beta blockers which she was hesitant to use so they remained untouched.
Instead she fasted on water for 4 days which got her on her feet and allowed her to walk unaided thereafter. She also replaced the oral spray with cayenne pepper (organic) to great effect.
Now she supplements with B3 (naicin), magnesium malate, vit c ~1gram/day, Vit D 2000 iu , multi vits, calcium, boric acid, virgin coconut oil.
Her diet is mainly vegetable with some meat. She avoids too much carbohydrate but when she does consume too much bread for example she experiences lethargy and angina.
Her progress has been remarkable considering that she has also continued to smoke during the past 2 years since her condition was identified. In her opinion her condition would have been normalised if she had ceased smoking permanently – hopefully this will be the case soon.
Her diet before her heart attack was high in sugars/carbohydrate.
Her diet now still contains fats but natural animal fats for the most part and coconut oil. Her stamina and ability to cope with strenuous exercise continues to improve while some of her friends of similar age and condition have significantly deteriorated after following courses of statins and beta blockers and maintaining a low fat diet.
Thanks for your articles – much appreciated
I am a psychiatrist from the UK with an interest in the effects of nutrition upon health in general but mental health in particular. I have become increasingly aware throughout my career of the influences on the practice of medicine of the pharmaceutical companies, those companies producing processed foods and the dairy industry. It is clear that a lot of money has been made by the manufacturers of margarine and polyunsaturated cooking oils, and by the pharmaceutical companies who peddle drugs aimed at the cardiovascular system and most notably Statins. I am appalled at the degree of influence that these bodies exert upon the medical profession and the number of people in the UK now who are on statins.
I am persuaded that the omega- six to omega three imbalance that existis in Western diets is a pernicious influence, as is the widespread use of sugar, margarine and dairy products. Cow’s milk is intended for baby cows and not for adult humans. The dairy industry of course tells us that we will suffer from calcium deficiency if we don’t have lots of milk and butter etc. What they don’t tell us is that in China where the consumption of dairy products is extremely low they have very little breast cancer whereas approximately 1 in eight women will develop it in the course of their lifetimes in the so-called Western world. I would like to congratulate Dr John Briffa and others who are publishing their thoughts regarding fat is nutrition in general and cardiovascular health, on the Internet.
There is also a theory that the Omega 6/ Omega 3 imbalance contributes to inflammatory conditions in general such as rheumatic conditions and the epidemic of depression in Western societies of the last 20 years which may be as a result of this switch to fats rich in omega six fatty acids. This rise in depression has done wonders for the balance sheets of pharmaceutical companies marketing SSRI antidepressants. If you’re not on a statin or an SSRI then there must be something wrong with you!
The health authorities are fully aware of the serious flaws and omissions in this meta-analysis. This study was funded by the National Dairy Council, dairy being the number one contributor of saturated fat in the U.S. and many other parts of the world. It was also conveniently published just before the USDA lowered the dietary recommendations of saturated fat for the first time in 20 years, from 10% to 7% of total calories.
Below is a section from the statement released by the European Heart Network in regards to their opinion of this meta-analysis, titled “European Heart Network position piece: Impact of saturated fat on cardiovascular disease obscured by over‐adjustment in recent meta‐analysis”
“However, the meta‐analysis (and an accompanying opinion piece by the same authors (4)) is compromised by a number of serious flaws and omissions. These are enumerated and discussed in detail in an editorial from Jeremiah Stamler (5). The most serious of these flaws is an over‐adjustment for serum cholesterol levels. The meta‐analysis involves data from 16 studies that evaluate the impact of saturated fat intake on CHD incidence or mortality, and 8 studies that evaluate the impact of saturated fat intake on stroke incidence or mortality. The authors state that ‘wherever possible, risk estimates from the most fully adjusted models were used in the estimation of the pooled [relative risks]’. It is well‐established that saturated fat intake is associated with increased level of serum cholesterol (6), and that serum cholesterol levels are associated with CHD and CVD (7). Therefore, serum cholesterol levels lie on the causal chain between saturated fat intake and CHD and CVD, and to adjust for serum cholesterol levels in a meta‐analysis will obscure the impact of saturated fat intake on these health outcomes. Yet 7 of the 16 studies included in the meta‐analysis of CHD events, and 4 of the 8 studies included in the meta‐analysis of stroke events were adjusted for serum cholesterol levels. These studies accounted for nearly half of all CHD and CVD events included in the meta‐analyses. Adjustment for serum cholesterol levels will inevitably bias the results of the meta‐analyses towards finding no association between dietary saturated fat intake and cardiovascular disease, but the authors do not mention this limitation in their article. As Jeremiah Stamler asserts in his editorial, what was actually found by the meta‐analysis was ‘a statistically non‐significant relation of SFA [saturated fat] to CHD… independent of other dietary lipids, serum lipids, and other covariates’ (5). A more appropriate and informative analysis would have included non‐adjusted associations between saturated fat and cardiovascular disease. An examination of the forest plots provided in the article shows that those cohort studies that did not adjust for serum cholesterol levels were more likely to find a positive association between saturated fat intake and cardiovascular disease, suggesting that a meta‐analysis of unadjusted data would likely produce positive results. “
References 5-7
(5) Stamler J. Diet‐heart: a problematic revisit. American Journal of Clinical Nutrition, 2010; 91: 497‐499.
(6) Clarke R, Frost C, Collins R, Appleby P, Peto R. Dietary lipids and blood cholesterol: quantitative meta‐analysis of metabolic ward studies. BMJ, 1997; 314: 112.
(7) Prospective Studies Collaboration. Blood cholesterol and vascular mortality by age, sex, and blood pressure: a meta‐analysis of individual data from 61 prospective studies with 55,000 vascular deaths. The Lancet, 2007; 370: 1829‐1839.
The full statement from the European Heart Network can be found here:
http://www.sydan.fi/lehtiarkisto/sydan_210/artikkelit/fi_FI/elainrasvat/_files/83538765767049682/default/EHN%20position%20piece%20-%20sats%20meta%20analysis.pdf
Below is a published study showing reversal of severe heart disease backed up with angiogram evidence.
http://www.heartattackproof.com/resolving_cade.htm
I wonder if Dr Briffa or anyone else could comment on the European Heart Network statement, suggesting flaws and bias in the WHO study?
The real reason we will not see a grand proclamation of the truth on this subject is due to economic issues. Medical schools could immediately change their tune on this subject if they wanted to but mainstream medicine is not in the business of health and healing, they are in the business of disease maintenance and symtoms management.
The main problem with telling people that saturated fat does not cause heart disease is the fact that people will want to reexamine the problem and want an answer as to what is really causing heart disease. Well that might lead people to Linus Pauling and others who have said that heart disease is nothing more than chronic low grade scurvy. If people realize that the cure is nothing more than vitamin C then that will be the end to a multi-billion dollar industry. I’m even open minded enough to believe that getting the cure out to the public might anger some of the population control nazi’s
thank you for sharing this information