Stearic acid is a long chain saturated fatty acid which contains 18 carbon atoms. According to an article in the Daily Mail:
“emerging evidence suggests not all saturated fat should be tarred with the same brush — one type of saturated fat, known as stearic acid, may actually protect the heart against disease.” (1)
However the rationale is based on the results of an investigation in which it was found that:
“the participants in the study experienced a 5 per cent drop in total cholesterol and around a 4 per cent drop in ‘bad’ LDL cholesterol “
In other words the conclusions depend on the “fact” that total blood cholesterol(TC) and the level of LDL cholesterol (the so-called “bad “one) are risk factors for heart disease. Hence it follows that saturated fats(SFA)which allegedly increase TC are undesirable and as a consquence the official recommendation is that we should reduce consumption. By contrast, polyunsaturated fats(PUFAs) reduce TC and are good: therefore consumption should be increased.
Unfortunately this is utter rubbish (See blogs 8 and 14). Here is a summary of some of the evidence to justify my statement:
- There is actually an “association” between the death rate from heart disease and TC which has only been observed in middle aged men. However an association does not prove cause and effect. In an area of high crime there may well be lots of police about (ie an association) but reducing the number of police will certainly not result in a reduction in the level of crime.
- Heart disease is not the only cause of death. If we consider total mortality we find that the death rate increases as the TC falls. This is because deaths from diseases such as cancers tend to increase as the TC is lowered.
- When we consider other sectors of the population including older men and women of all ages the relationship between TC and heart disease is totally different from that observed in middle-aged men. In a Norwegian study, 52,087 men and women were monitored for 10 years. In men aged 60 and over the death rate for TC 5-6 was 16.2 and for those below 5 the death rate was 20.3. For women the value for TC 5-6 was 10.3 but below 5 it was more than double this figure at 22.3(2) According to NHS guidelines a TC above 5 is regarded as too high!
- What is particularly relevant is that over about 65 years old the higher the TC level the greater the life expectancy. This finding has been replicated many times.
There have been a number of attempts to assess the various relevant research studies on this topic. Uffe Ravnskov conducted an analysis of 27 groups of patients and controls involving over 150,000 participants. He found that in 3 of these those with CHD had consumed more saturated fat than the controls and that in one they had consumed less. However the differences were extremely small. In the remainder no differences could be detected(3).
The Cochrane Collaboration conducts systematic reviews of primary health care and health policy. Al relevant research reports are critically assessed and only included if they conform to stringent criteria. Steps are taken to ensure that any bias or random error is strictly limited hence it has established a unique reputation for producing reports which are internationally recognised as meeting the highest standards of evidence-based health care.
A Cochrane review of the role of the relation between the various fats and heart disease it was concluded that:
“Despite decades of effort, and many thousands of people randomized, there is still only limited and inconclusive evidence of the effects of modification of total, saturated, monounsaturated or polyunsaturated fats on cardiovascular morbidity and mortality(4)”
In a report prepared by an FAO Expert Group it concluded that:
“The available evidence from cohort and randomized controlled trials is unsatisfactory and unreliable to make judgements on the effect of fat on the risk of Coronary Heart Disease(5)”
Despite the fact that official bodies persist with the advice to limit the consumption of saturated fat it now obvious to anyone who views the evidence dispassionately that there is absolutely no justification for the recommendation.
In reality it is quite unbelievable that it should ever have been advocated for the simple reason that the term “saturated fats” actually consists of a range of chemical entities It is totally unacceptable to suggest or imply that all of these are likely to have identical functions in the body. In any event the investigations which were designed to determine the role of SFA on the level of cholesterol in the blood were unbelievably bad. Invariably there was no attempt to control the detailed composition of the “saturated fat”. In some cases the “saturated fat” contained trans fats, which are known to be damaging to health. When studies were done with individual fatty acids it was found that there was no consistent effect on blood cholesterol levels, thereby providing confirmation that all the different fatty acids do not function in exactly the same way.
It is salutary to reflect on the fact that the original target to reduce SFA by 25% which was set in 1984 was reached some years ago and a fat lot of good that has done. Obesity continues to increase but even more worryingly diabetes has doubled in the last 15 years and is projected to go on rising. Those with diabetes are much more likely to develop high blood pressure, heart disease and Alzheimer’s Disease than those without.
There is considerable evidence which demonstrates that most of the SFAs are needed by the body for optimum nourishment(See Blog 16). Regrettably those who attempt to implement the official advice aredoing themselves more harm than good.
If you would like to gain further insight into this subject I recommend you watch an excellent Powerpoint lecture by Peter Attia, an American medic. You can find it at:
- H Petursson et al(2012). Journal of Evaluation in Clinical Practice 18 (1) pp 170-171
- U. Ravnskov(1998) Journal of Clinical Epidemiology 51 443-460
- C. Hooper et al. (2001).Dietary fat intake and prevention of cardiovascular disease: systematic review. British Medical Journal 322, pp757-63
- FAO (2010)“Fats and Fatty Acids in Human Nutrition”. Report of an Expert Consultation. FAO Food and Nutrition Paper 91.