The Cholesterol Myths by Uffe Ravnskov, M.D., Ph.D.

8. How to create a false idea

How a ”fact” is created by misquoting unsupportive findings and exaggerating trivial findings is examplified in section 1, the story about the so-called ”good” and ”bad” cholesterol.

Observations that are totally devastating for the diet-heart idea are mostly ignored. A good example is the fact that if we exclude individuals with the rare disease familial hypercholesterolemia (less than 0.5 percent of mankind suffer from it) there is no association between the level of blood cholesterol and the degree of vascular atherosclerosis (section 2).

Another one. Before the statin-era overviews of all cholesterol-lowering trials have shown that mortality cannot be improved by lowering cholesterol. But diet-heart proponents usually mention the trials with a positive outcome only and ignore the trials with a negative outcome.

 

Thus, in 16 trial reports published between 1970 and 1992 a total of 40 citations were to (apparently) supportive or inconclusive trials, but with one exception, not a single citation was to unsupportive trials, although the number of supportive and unsupportive trials were equal (79).

It is interesting to compare the number of citations of papers published in the same journal because few citiations of a paper may simply reflect that it has been published in a little-known or less reputable journal. In 1984 The Lipid Research Clinic´s coronary primary prevention trial was published in JAMA (110). In that trial 32 of the patients whose cholesterol was lowered died from a heart attack against 44 of the patients in the untreated control group. The total number of deaths (deaths from all causes) was 68 treated patients against 71 patients in the control group. These figures were not statistically significant by conventional statistics, but in spite of that the result was used as the main argument by the American cholesterol campaign.

In 1985 Dr. Miettinen and colleagues from Helsinki, Finland published another, but smaller cholesterol-lowering trial in the same journal (111). In that trial four patients whose cholesterol was lowered died from a heart attack, whereas only one died in the untreated control group, and the total number of deaths was ten in the treatment group against five in the control group.

Thus, both papers dealt with the same subject and were published in the same journal and no one has questioned the honesty of the experimenters or the quality of the studies. Reasonably, they should have been cited almost equally often. That the LRC trial, at least according to its directors, was supportive, and the Miettinen trial was not, is unimportant because the aim of research is to find the truth, whether it is happy or not. Here you can see how often the two papers have been cited by other scientists during the first four years after their publication:

 

	Miettinen and co-workers	LRC-study
First year Second year Third year Fourth year	6 5 3 1	109 121 202 180

(Data according to Science Citation Index)

Needless to say, the paper by Miettinen has been cited mainly by more critical scientists.

An example of an unsupportive study which has been cited, many, many times, as if it was supportive is the Japanese migrant study. In Japan coronary heart disease is uncommon, allegedly due to the lean Japanese diet. A large study of Japanese emigrants (112) is often used as evidence because after migration to the United States, where the food generally is much fatter than in Japan, the serum cholesterol of these emigrants increased and they died from heart attacks almost as often as did Americans. The increased coronary mortality after migration was not associated with the diet or the serum cholesterol, however, but with the cultural upbringing: those who lived according to Japanese traditions were protected against heart attacks.

 

Especially striking was the finding that emigrants who stuck to the Japanese tradition, but ate American food ran a smaller risk of heart disease than emigrants who were accustomed to the American way of life but ate Japanese food (113).

Here is another example. A common message from the American Heart Association and The National Heart, Lung, and Blood Institute to doctors is that there exist a close correspondence between degree of cholesterol lowering and degree of mortality reduction. Listen for example to the words from The Cholesterol Facts (114): ”The results of the Framingham study indicate that a 1% reduction of cholesterol corresponds to a 2% reduction in CHD (coronary heart disease) risk.” This statement was followed by a reference to a paper which reported the 30 years experience from Framingham (115).

But in that paper you can read the following statement:

”For each 1 mg/dl drop of cholesterol there was an 11% increase (!) in coronary and total mortality.”

The above examples are just the tip of the iceberg. Here is a systematic review of the way the three largest, authoritative reviews have misquoted the literature:

Ravnskov U. Quotation bias in reviews of the diet-heart idea. J Clin Epidemiol 1995; 48: 713-9.

More recent examples of false citations are given in the following papers:

Ravnskov U, Allan C, Atrens D, Enig MG, Groves B, Kaufman J, Kroneld R, Rosch PJ, Rosenman R, Werkö L, Nielsen JV, Wilske J, Worm N. Studies of dietary fat and heart disease. Science 2002; 295:1464-1465.

Ravnskov U. The diet-heart idea is kept alive by selective citation Rapid Response BMJ 8. Dec 2003

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