Lipid Nutrition Guidelines - Ohara, Naoki

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Résumé :
Ever since the publication of Ancel Keys' watershed 'Seven Countries Study' in 1970, medical thinking has posited a causal link between the intake of animal fats and coronary heart disease. The research of Prof. Harumi Okuyama and his colleagues presented in this new publication suggests that this link is in fact tenuous. It goes beyond that to suggest that current medical wisdom regarding lipid nutrition may actually be counterproductive. This ground-breaking analysis is likely to be debated for many years to come. The 'Seven Countries Study', which identified the specifics of the Mediterranean Diet and awarded it a central position in combating coronary heart disease, triggered significant changes in Western diets. Most notably, it stimulated a widespread attempt to reduce animal fats and replace them with vegetable fats. The low-density lipoprotein (LDL) element of the cholesterol naturally present in animal-source foods was dubbed a killer, and a significant industry developed around the provision of plant-based oils and fats. The clinical consensus on cholesterol was further strengthened in 1987 by the introduction of statins, an innovative class of drugs that reduce LDL production in the liver and are designed to help guard against coronary heart disease. Thirteen Nobel Prizes have been awarded to scientists who devoted major parts of their careers to cholesterol research. It is therefore a brave research team that dares to challenge the link between animal fats and coronary heart disease. This, however, is precisely what Prof. Okuyama and his team set out to do in this book. They actually recommend increasing the intake of cholesterol and animal fats, to an extent that does not lead to obesity. This recommendation is based on the discovery by Prof. Okuyama and his team that common vegetable oils such as canola and hydrogenated vegetable fats have toxic effects. They demonstrate that hydrogenated vegetable fats and oils are important culprits in atherosclerosis and other lifestyle diseases, and suggest that high total or LDL-cholesterol is not the cause of atherosclerosis or cardiovascular disease. Further, they argue that current medical guidelines on lipid nutrition conflict with evidence-based research, and that persistently focusing on LDL-cholesterol as the cause of atherosclerotic cardiovascular disease (ASCVD) is counterproductive....

Biographie:
Harumi Okuyama received his Ph.D. from the University of Tokyo. He held the positions of Research Assistant at the University of Tokyo, Associated Professor and Professor at Nagoya City University (1972-2005), and Professor at the School of Pharmacy, Kinjo Gakuin University (-2012). He later returned to research as a visiting researcher at the Institute of Consumer Sciences and Human Life (2012-). During that time, he also served as a visiting professor at Baylor College of Medicine (Houston, TX), University of Illinois at Chicago (Chicago, IL), Dalian College of Medicine, Dalian University (Dalian, China), and The University of Toyama (Toyama, Japan). Following his participation in the founding of the Japan Society for Lipid Nutrition, he served as the Society's first President. In this role and while continuing basic and clinical research into fats and oils, he strove to convey to the next generation the true information known about lipids and which oils were safe for consumption based on the latest evidence available. He also served as Chairman of the NGO Japan Council for the Safety Evaluation of Fats and Oils in Foods. He started his research career as a graduate student of the University of Tokyo, focusing on identifying fatty acid synthetases as thermo-receptors to alter the chain length and/or the degree of unsaturation of fatty acids produced in vitro depending on the temperature in some microorganisms. Using animal models, he contributed to revealing the mechanisms of biosynthesis of membrane phospholipids with different fatty acids at the 1- and -2 positions. He then extended his research interests to estimating the nutritional values of various fatty acids. His group reached the following conclusions. (1) Plasma high cholesterol is a predictor of longevity. (2) Medicines to lower the LDL-C/HDL-C ratio do not bring about beneficial effects on atherosclerotic diseases when the objective endpoint of mortality is used. (3) The action mechanisms of statins involve the inhibition of isoprenyl intermediate formation and the inhibition of mitochondrial ATP generation. (4) In a stroke-prone rat model, certain types of common vegetable oils (e.g., canola, olive, and hydrogenated soybean oils) were found to accelerate cerebral bleeding, kidney inflammation, decreasing platelet counts, and decreasing tissue levels of testosterone. (5) These toxic oils share the same mechanism of action as statins and warfarin. (6) While some European countries have steadily increasing populations, many Mediterranean and East Asian countries, particularly Japan, are experiencing serious problems with decreasing birth rates and declining populations. Prof. Okuyama and his group have presented scientific evidence that the decreasing birth rate in Japan is correlated with increased intake of some types of vegetable oils, and thus the current, authoritative, mainstream lipid guidelines from the World Health Organization, backed by academics and industry-oriented people, are the major cause of the rapid decline in the Japanese population. Alongside the coauthors of this work and other scientists and clinicians who acknowledge the scientific evidence available, Prof. Okuyama recommends restricting the intake of vegetable fats and oils demonstrated to have toxic effects in animal models and increasing the intake of cholesterol and animal fats to an extent that does not lead to obesity....