Part 1: Unsaturated fats
You don't have to look very far to find the evidence that unsaturated fats are dangerous. Studies go right back to 1945, when a scientist named Rausch at the University of Wisconsin noticed that rats which had corn oil added to their diets had more cancers.
That observation alone should have ensured that there was a thorough investigation of unsaturated fats before they were applied to humans. Yet no such trials were ever done.
Over following years, several scientists highlighted increased numbers of cancers in people with highly polyunsaturated diets.
In 1957, Dr D Harman, an investigator from the Veterans' Hospital in San Francisco, advised caution with the use of polyunsaturated fats in human diets because of the cancer-producing compounds that could result from their auto-oxidation. He pointed out that the Japanese had much more stomach cancer which, he suggested, was because of the polyunsaturated fats in the fish the Japanese ate.
In the 1960s an 8-year study was conducted at the Veterans' Hospital, San Francisco, to look into the benefits of polyunsaturated fats for the prevention of cardiovascular disease. The results were published in 1971. The study scientists split war veterans into two groups for the study. One group ate their normal diet with animal fats, while the other group's diet was high in polyunsaturated fats. During the study, careful records were kept and autopsies were performed to verify causes of death.
The results showed that there were a few more deaths from heart attacks among the men on the saturated fats, but this was unremarkable as variations in numbers of this sort were not unusual.
What was far more important was that there were almost twice as many deaths from cancer in the polyunsaturated fats group. This did come as a surprise, for deaths from cancer do not show the variation that is seen with heart attacks. Not surprisingly, this study questioned the advisability of using polyunsaturated fats.
But there is another question hanging over this paper: it was not published in an American journal, but an English one. I have to wonder: was it refused publication in the USA?
And, if so, why?
There have also been many other studies on both animals and humans which have shown the unhealthiness of polyunsaturated fats and oils.
1. Rausch HP, Kline BE, Baumann CA. The influence of calorie restriction and of dietary fat on the tumor formation with ultraviolet light. Cancer Res 1945; 5: 431.
2 Harman D: Atherosclerosis: possible ill-effects of the use of highly unsaturated fats to lower serum cholesterol levels. Lancet 1957; II: 1116.
3. Pearce ML, Dayton S. Incidence of cancer in men on a diet high in polyunsaturated fat. Lancet 1971; I:464-7.