The role of dietary polyunsaturated fats in heart disease and atherosclerosis

Townsend Letter for Doctors and Patients, August-Sept, 2003 by Wayne Martin

Now let us look at the possibility that the GOOD polyunsaturated fatty acids are a major cause of myocardial infarction. I had a long exchange with Professor Terence Anderson, then of the University of Toronto, but later at the University of British Columbia.

The New Oil Seed Industry Grew to Multi-Billion Dollar Industry

Anderson had noted that as the new oil seed industry was founded in the mid-1920s and grew in size to a multi-billion dollar industry, deaths from myocardial infarction increased in direct numbers with the sale of this industry's product, the new polyunsaturated fats such as corn, soya, cotton and sunflower seed oils and the margarines made from them.

In the period of 1925 to 1935, most of the liquid fats that they produced were converted to solid margarine. Before these liquid fats will harden in the hydrogenation process, the tocopherol antioxidants had to be removed.

Anderson says that the orthodox concept is that myocardial infarction is caused by coronary blood clots preventing enough oxygen getting to the myocardium. He says that these polyunsaturated fats from which the antioxidants have been removed, are changed in the body to form peroxide fats. He gives one reference to corn oil from which the antioxidants have been removed being cardiotoxic to animals.

He said that these oxidized polyunsaturated fats act on the myocardium to have the effect to cause muscular dystrophy of the myocardium. He says that in this case the heart is damaged by too much oxygen, that this peroxide damage to the heart can be seen if pathologists will take the trouble to look for them, as small fibrotic foci of degeneration in the myocardium. He said that these small foci will start a heart attack. He had a report in The Lancet (1973, ii, 912-14) with the title "Nutritional Muscular Dystrophy and Human Myocardial Infarction."

Anderson, in an article in New Scientist for February 9, 1978, told how the change from whole grain bread to bleached white bread in about 1900 caused a major increase in death from myocardial infarction. The tocopherol antioxidants in whole grain bread were preventing the oxidation of the polyunsaturated fatty acids; in the bleaching of white flour, the tocopherols are destroyed.

He gave an example. In 1919 Italy banned the use of bleached white flour to reduce the importation of wheat until 1946. Bread in Italy was whole grain during this period of 27 years and there was no increase in deaths from myocardial infarction in Italy whereas in England and the USA there had been a large increase in deaths from myocardial infarction.

Now to the Ireland-Boston Brothers Heart Study. This study was done by Dr. Fredrick Stare, Professor of Nutrition at the Harvard University School of Public Health. Stare found brothers where one had migrated to Boston and one had remained in Ireland.

Ireland had a dairy industry that was being protected from the competition of the low priced polyunsaturated fats by a large tax on them. The brothers in Ireland had in diet one and a half pounds of butter a week and almost none of the GOOD polyunsaturated fats. The brothers in Boston were living on something very close to the Prudent Diet with much less of the BAD saturated fats in diet and much more of the GOOD polyunsaturated fats. If the Prudent Diet was right, the brothers in Ireland should be having more heart attacks. What was found was just the opposite, with more heart attacks among the brothers in Boston. Stare's report was in World Review of Nutrition and Dietetics vol 12, 1970.