A partial release of the results of MCS study was made in a 1989 paper in the journal Arteriosclerosis with Frantz as lead author. This paper made the modest conclusion that: “For the entire study population, no differences between the treatment (high linoleic acid group) and control (high saturated fat group) were observed for cardiovascular events, cardiovascular deaths, or total mortality.” (Frantz et al. 1989).
The results of the MCS study did not give the expected results and directly contradicted the conclusions of the Seven Countries Study which Keys had published a few years earlier in 1986. Although Keys was a co-proponent of the MCS study, his name did not appear as a co-author in the Arteriosclerosis paper; he was not even mentioned in the Acknowledgment. This might also explain why it was published in a journal of more limited circulation which gave it less exposure. It is clear that a wider distribution of the results of the Arteriosclerosis paper, with Keys properly included as co-author, would have been fatal to the saturated fat-cholesterol-heart disease hypothesis.
Influence on WHO Policy
The World Health Organization has adopted the saturated fat-cholesterol-heart disease hypothesis. For example, the WHO Healthy Diet Fact sheet No. 394 reads: “For adults. A healthy diet contains…less than 30% of total energy intake from fats. Unsaturated fats (e.g. found in fish, avocado, nuts, sunflower, canola and olive oils) are preferable to saturated fats (e.g. found in fatty meat, butter, palm and coconut oil, cream, cheese, ghee and lard) …” (WHO 2015).
This WHO report was taken from a publication of the Food and Agriculture Organization, Fats and Fatty Acids in Human Nutrition Report of an Expert Consultation. However, on page 9 of this publication, the following limitation was stated:
“The Expert Consultation recognizes that grouping of fatty acids into these three broad groups (SFA, MUFA and PUFA) is based on chemical classifications, but it is clear that individual fatty acids within these groups have distinct biological properties. However, most of the epidemiological evidence reviewed by the experts uses broad groupings, which makes it difficult to distinguish and disentangle the effects of individual fatty acids.
“SFA refers to the major SFA in our diet, namely C14, C16, C18, except in the case of milk and coconut oil where SFA range from C4 to C18” (FAO 2008).
The experts ignored the distinction between medium-chain and long-chain fat. This distinction is central to the understanding of the health effects of coconut oil, which is made up of about 63% medium-chain fat. The failure to recognize this difference makes this document’s conclusions regarding coconut oil incorrect.
The Role of Coconut in Traditional Healthy Diets
There is abundant evidence that people who abandon their traditional coconut diets in favor of the American diet have become overweight or obese. WHO (2003) reported that Pacific islanders “were 2.2 times more likely to be obese and 2.4 times more likely to be diabetic if they consumed fat from imported foods rather than from traditional fat sources. The most commonly consumed imported foods providing fats were identified as oil, margarine, butter, meat and chicken, tinned meat and tinned fish.” Traditional fat sources in the Pacific islands are coconut, fish and pork.
A 1999 study among American Samoans showed that a shift to a modern diet increased their carbohydrate and protein consumption and decreased their overall fat, in particular, saturated fat. This shift was identified as the cause of their increased incidence of obesity and cardiovascular disease (Galanis et al. 1999).
Evidence from Polynesia and the Philippines show that there is no link between coconut oil consumption and cardiovascular disease. In the Polynesian islands of Pukapuka and Tokelau, Prior (1981) reported that: “Vascular disease is uncommon in both populations (Pukapuka and Tokelau) and there is no evidence of the high saturated fat intake having a harmful effect in these populations.” Likewise, a population-wide study by Florentino & Aguinaldo (1987) in the Philippines showed that: “High coconut oil intake is not consistent with high CVD mortality rate.” They then concluded that: “These observations do not seem to corroborate the contention that coconut oil as naturally ingested in the diet together with other fat sources increases the risk of CVD.”
Conclusions and the Way Forward
Ancel Keys’ landmark Seven Countries Study became the basis for the recommendation of the Dietary Guidelines for Americans to consume a low-fat diet and to replace saturated fat by unsaturated fat. This is currently being put to question. Further, Keys’ study covered primarily animal fat which is mainly long-chain fat and is not applicable to a predominantly medium-chain fat, such as coconut oil. Therefore, the basis for Keys’ inclusion of coconut oil is incorrect.
Historical documentary evidence of the significant influence of the American sugar industry and a detailed analysis of published and unpublished research on dietary fat show that the current dietary recommendations for a low-fat diet and replacement of saturated fat with polyunsaturated fat are wrong and heavily influenced. Populations that have followed these recommendations have become significantly overweight and obese. Coconut oil has been labeled as unhealthy because of its high saturated fat composition. However, populations that consume significant amounts of coconut do not have high rates of obesity and heart disease. The Keys saturated fat-cholesterol-heart disease hypothesis has been shown to be in error in numerous studies, and significantly, in a study which Keys himself did not publish. This hypothesis should be abandoned.
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