Scandalous discovery: scientists 40 years hid the results of the study Bashny.Net

In 1968 scientists from Minnesota have launched a large study, "Minnesota Coronary Experiment". The purpose of the study is experimental verification of lipid, or cholesterol, the theory served as a basis for official dietary recommendations of the last decades. The basis of this theory (also known as the diet-heart hypotes) lays a postulate that the cause of cardiovascular disease — elevated cholesterol levels in the blood, and the key to health and longevity — low cholesterol.

According to this hypothesis, food containing saturated fats and cholesterol — meat, fatty dairy products, egg yolks — declared harmful and one of the fundamental principles of a healthy diet proclaimed the replacement of saturated animal fats with polyunsaturated vegetable oils and Margarines. In 1980, the principle was officially enshrined in the American dietary recommendations (Dietary Guidelines), which made him the de facto dogma for all industrialized countries.

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That such substitution actually leads to lower levels of cholesterol and low-density lipoprotein (LDL) has been identified by many studies, but the claim that it will reduce the risk of cardiovascular diseases and General mortality rates, remains unproven, although common, hypothesis. The Minnesota experiment was to prove this conjecture.

This was the largest study ever in this area: lasted four and a half years (1968-1973), participated 9,423 men and women aged 20 to 97 years. They were all patients in psychiatric institutions of the closed type, which makes this study extremely dubious from the point of view of modern scientific ethics, but it has allowed scientists to carefully monitor their diet.

Study participants were divided randomly into two groups. Diet control group was standard for the time: 4,7% calories gave linoleic acid (the main component of most vegetable oils, is of a type omega-6) and 18.2% of calories — saturated fats from butter, milk, meat and other animal products.

Diet had to conform to the standard American diet, so to call it particularly healthy, it is impossible — for example, it contained quite a large number of a normal time for a TRANS fat — about 3.2% of energy.

The experimental group followed a special cholesterin-lowering diet. Amount of saturated fat in the experimental group was halved to 9.2% of total calories, but the amount of linoleic acid, mainly from corn oil had almost tripled — to 13.2% of calories. The amount of TRANS-fats have been reduced, although it is not clear how. The time sequence of the experimental diet was restricted to the period of stay of the member in the hospital. 2,355 participants were dieting at least a year.

The study was double-blind neither the organizers nor the participants knew the experiment what kind of diet is observed. The patients received food in special containers with digital codes and didn't know what she cooked fats. There was even a special designed indistinguishable from each other Margarines with different levels of saturated and unsaturated fats.

It was in all respects a Grand, carefully planned and executed scientific work. The more surprising is the fact that its full results were hidden from the public for decades — as if the authors themselves didn't want to publish them. Partial results were presented in 1975 at the conference of the American heart Association (AHA), and published — partly — much later, in 1989, in a highly specialized medical journal Arterosclerosis and there were few who noticed.

If you read the original publication in 1989, it becomes clear why the authors did not hurry to share with the world the results of their work. Yes, they achieved their goal and proved that following a specially designed diet lowers cholesterol levels.

The experimental group reduced c 207 mg/DL (5,35 mmol/l) up to 175 mg/DL (4.5 mmol/l). But, as the authors note in the conclusion, they found no difference in overall mortality and frequency of cardiovascular disease between the control and experimental groups, although he noted some "positive trend" among the younger age groups. In other words, cholesterol decreased, but this did not benefit the study participants.

As it turns out, everything was even more serious. A team of us scientists led by Christopher Ramsden-examined the original data and the results of this study — at least those that have survived to our time (largely due to the fact that they were used in some graduate student's work in 1981). The results of their work were published recently in the prestigious medical journal BMJ. It turned out that the connection between lowering cholesterol and total mortality was still. But this relationship was inverse: the more decreased the cholesterol, the higher was the mortality. This pattern was most significant in patients older than 65 years — i.e. those whose risks of cardiovascular disease were highest. Here is one of the published charts (the rest can be found in the original publication in the BMJ):

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The vertical axis mortality, horizontal — number of days of following a special diet. Red line — control group, blue — experimental. In patients older than 65 years, the decrease of cholesterol at 30 mg/DL was associated with an increased risk of dying by 35%.

For younger participants the reduction of cholesterol really associated with a minimal and statistically insignificant decrease in mortality rates (those "positive trend"), but the results for the full sample still provided that the replacement of animal fats with vegetable oils has increased and the mortality and morbidity.

"Partial publication led to the fact that the benefits (of vegetable oils) have been overstated and the potential risks are underestimated" — the authors of a new study. "If the data was published 40 years ago," says Daisy Zamora from the University of North Carolina — «this could change the trajectory of research in the field of nutrition and heart and dietary recommendations.»

But the authors of the Minnesota experiment, among whom was the founder and chief lobbyist of the lipid theory of Ansel Keys, chose to hide the results of their own work to the table and ignore their existence.

One of the consequences of the decision, the modern diet is saturated in linoleic acid. In the U.S. Dietary recommendations is still present daily intake to 5 teaspoons (27 grams) of vegetable oils, most of which mainly consists of linoleic acid. Many modern scholars seriously doubt the correctness of this approach.

Refined vegetable oil is a relatively recent invention. As the authors of the article in BMJ, 100 years ago in the traditional diet was no more than 6 grams of linoleic acid per day received by people from whole foods — nuts, seeds, etc. Now the consumption of vegetable fats has increased significantly.

Many studies link high intake of linoleic acid from chronic inflammation and oxidation of lipoprotein particles (5, 6). Paradoxically, the consumption of vegetable oils total cholesterol decreases, but the cholesterol becomes much more dangerous for your health. Nevertheless, for decades the food industry has promoted vegetable oils and Margarines as products for a healthy heart ("heart healthy").

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Interestingly, this is not the first case of its kind. In 2013, Christopher Ramsden conducted a similar analysis of unpublished data of another study — Sydney Diet Heart Study (1966-1973), whose participants were 458 men aged 30 to 59 years, who recently had cardiovascular disease. They also were instructed to replace saturated fats with polyunsaturated omega-6 predominantly from safflower oil. The result is similar — increased mortality and incidence of re - ... and many years of silence this inconvenient fact.

The conclusion is quite sad: decades, the world followed the official advice on nutrition, based on distorted and incomplete data scientific research. Whether it was the result of an honest mistake or deliberate dishonesty of scientists, we will likely never know — the authors of the Minnesota study is no longer alive. But the recommendations in the field of saturated and unsaturated fats obviously time to reconsider.published  

 

See also: It's a heady feeling: the role of adrenaline in our lives

How the brain decides when we sleep and when to Wake up

 

P. S. And remember, only by changing their consumption — together we change the world! ©

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Source: lchf.ru/11078