Now that we know a little of cholesterol’s role in the body and how important it is to the health of our cells and production of hormones, we can now ask some intelligent questions concerning the allegations against this essential sterol. We’ve been conditioned to equate cholesterol with clogged arteries and heart attacks and yet the plaques lining the inside of blood vessels contain other substances such as white blood cells, calcium, platelets, and more. Cholesterol is not even the principle component of arterial plaque. Protein, mostly as scar tissue, is more abundant (Faculty and Disclosures, 2008).
If this be the case, and it is, what is the significance of cholesterol numbers in the blood and what causes these numbers to rise?
The prevailing hypothesis is that eating foods high in cholesterol and fats will raise these levels and cause a higher incidence of cardiac heart disease (CHD), stroke and cardiovascular disease (CVD). However, as we showed in the previous article that cholesterol is poorly absorbed, why do researchers continue to tell us that eating these types of foods are bad, especially since studies abound that prove quite the contrary?
Let us look at a few shall we?
Adelle Davis states in Let's Gets Well, "Animals that are fed sugar instead of unrefined carbohydrates develop high blood cholesterol levels. The blood cholesterol of healthy volunteers (Human) fell when they ate unrefined carbohydrates, but substituting sugar caused their blood triglycerides and cholesterol levels to increase markedly." (Davis, 1965)
The Framingham Heart Study was established in 1947 and is still going on today. The researchers worked from the premise that elevated blood cholesterol levels were due to the amount of cholesterol consumed. The table below shows that men consuming a wide range of cholesterol showed no relationship between the amount eaten and blood levels, while women who consumed more cholesterol had lower blood levels.
Next, these scientists studied intakes of saturated fats but again they could find no relation. There was still no relation when they studied total calorie intake. They then considered the possibility that something was masking the effects of diet, but no other factor made the slightest difference.
After twenty-two years of research, the researchers concluded: "There is, in short, no suggestion of any relation between diet and the subsequent development of CHD in the study group."
Since they could not link the intake of saturated fats and elevated blood cholesterol, they had to revise their hypothesis:
"This hypothesis, however, depends on the presence of a strong direct association of fat intake with coronary heart disease. Since we found no such association, competing mortality from coronary heart disease is very unlikely to explain our results."
In a study published in the British Medical Journal, 1965, patients who had already had a heart attack were divided into three groups: one group got polyunsaturated corn oil, the second got monounsaturated olive oil and the third group was told to eat animal fat. After two years, the corn oil group had 30 percent lower cholesterol, but only 52 percent of them were still alive. The olive oil group fared little better–only 57 percent were alive after two years. But of the group that ate mostly animal fat, 75 percent were still alive after two years (British Medical Journal 1965 1:1531-33).
A study of 61,471 women aged forty to seventy-six, conducted in Sweden, looked into the relation of different fats and breast cancer. The results were published in January 1998. This study found an inverse association with monounsaturated fat and a positive association with polyunsaturated fat. In other words, monounsaturated fats (olive oil [natural oils not chemically processed such as: canola, sunflower and sesame] some nuts, avocados, etc.) protected against breast cancer and polyunsaturated fats (soybean oil, corn oil, canola oil and sunflower oil, as well as fatty fish such as salmon, mackerel, herring and trout) increased the risk. . (Alicja Wolk, et al., 1998)
The Anti-Coronary Club project, launched in 1957 and published in 1966 in the Journal of the American Medical Association, compared two groups of New York businessmen, aged 40 to 59 years. One group followed the so-called “Prudent Diet” consisting of corn oil and margarine instead of butter, cold breakfast cereals instead of eggs and chicken and fish instead of beef; a control group ate eggs for breakfast and meat three times per day. The final report noted that the Prudent Dieters had average serum cholesterol of 220 mg/l, compared to 250 mg/l in the eggs-and-meat group. But there were eight deaths from heart disease among Prudent Dieter group, and none among those who ate meat three times a day (JAMA 1966 Nov 7; 198 (6):597-604; Bulletin NY Academy of Medicine 1968).
An 11 year study conducted in New Zealand with 630 people aged 25 to 74 measured cholesterol levels at initial examinations and whether they were alive or dead at the end of the study. The causes of death were divided into three categories: cancer, cardiovascular disease, and "other." What they found was those with lower cholesterol levels had higher rates of death in all three categories (R Beaglehole, 1980).
There is a much higher butter consumption in Western France than in Eastern France, yet the rate of mortality from ischemic heart disease in Western France is almost half that among men in Eastern France (MacLennan & Meyer, 1977). We find the same situation in India. The incidence of acute myocardial infarction is seven times higher in southern India than in northern India; however, in southern India, dietary fat provides only 3.5 percent of total calories, 45 percent of which is polyunsaturated. In northern India, dietary fat provides 23 percent of total calories, only 2 percent of which is polyunsaturated (Malhotra, 1967).
A meta-analysis was conducted on studies that followed 347,747 subjects for a period of 5-23 years. These studies were to determine the increased risk of saturated fat intake on CHD, stroke or CVD. Their conclusion? “That there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD.” (Patty W Siri-Tarino, 2009)
One more point of interest should be included before signing off. The rise of CHD in Britain at the turn of the century was dramatic to say the least. It was during this time that margarine and vegetable shortenings became a substitute for butter due to the rise in cost. Here is a telling comparison of the increase of CHD and increased intake of margarine and vegetable shortenings.
I must conclude this portion of my report, but let us consider the import of the studies that have been cited. Understand that there are many more just like these that fly in the face of what we are being told through the media and pharmaceutical companies concerning cholesterol and fats. In my next article we will look at the real causes of high cholesterol and why plaque is formed in the arteries.
Works Cited
Alicja Wolk, P., Reinhold Bergström, P., David Hunter, M., Walter Willett, M., Håkan Ljung, M., Lars Holmberg, M., et al. (1998, January 12). A Prospective Study of Association of Monounsaturated Fat and Other Types of Fat With Risk of Breast Cancer. Retrieved from JAMA Internal Medicine: http://archinte.jamanetwork.com/article.aspx?articleid=190898
Davis, A. (1965). Let's Get Well. San Diego: Harcourt Brace Jovanovich.
Dikkers, A., & Tietge, U. J. (2010, December 21). Biliary cholesterol secretion: More than a simple ABC. Retrieved Janurary 16, 2015, from World J Gastroenterol: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3007110/
Faculty and Disclosures. (2008). In Vivo Coronary Plaque Classification by Intravascular Ultrasonography: Plaque Components. Retrieved from Medscape: http://www.medscape.org/viewarticle/570565_4
MacLennan, R., & Meyer, F. (1977). Food and Mortality in France. Lancet, 133.
Malhotra, S. (1967). Graphic aspects of acute myocardial infarction in India with special reference to pattersns of diet and eating. British Heart Journal, 337-344.
Patty W Siri-Tarino, Q. S. (2009, November 25). Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Retrieved from The American Journal Of Clinical Nutrition: http://ajcn.nutrition.org/content/early/2010/01/13/ajcn.2009.27725.abstract
R Beaglehole, M. A. (1980, Feburary 2). Cholesterol and mortality in New Zealand Maoris. Retrieved from The BMJ: http://www.bmj.com/content/280/6210/285.abstract
Ravnskov, U. (1992, August 29). Cholesterol lowering trials in coronary heart disease: frequency of citation and outcome. Retrieved from theBMJ: http://www.bmj.com/content/305/6844/15?variant=abstract