The Sydney Diet Heart Study was designed to evaluate the effectiveness of replacing dietary saturated fat with omega-6 linoleic acid for secondary prevention of coronary artery disease and death.

The study, which was published in the British Medical Journal, involved 458 men ages 30 to 59 who had experienced a heart attack or angina.

The treatment group was instructed to increase their intake of polyunsaturated fatty acids while reducing their saturated fatty acids. The control group was given no dietary instructions.

The treatment group was given safflower oil and polyunsaturated margarine. Liquid safflower oil was substituted for animal fats and taken as a supplement.

Polyunsaturated margarine was used in place of butter.

Compared to the control group, the treatment group had a 38 percent increase in all-cause mortality and a 30 percent increase in cardiovascular mortality.

The authors concluded, “These findings could have important implications for worldwide dietary advice to substitute [polyunsaturated fats] for saturated fats.”

For many years people have been told to substitute saturated animal fats for polyunsaturated fats made from plants.

What are the consequences of this advice? We have become the most obese people on the planet, and have more cancer and heart disease than ever before. I have no doubt that most chronic illnesses as well as obesity are driven by eating this unhealthy diet.

Animal fat and protein have been staples of human subsistence since the dawn of mankind. We simply need the nutrients found in animal products.

Saturated fat has been demonized by the American Diabetes Association and the Academy of Nutrition and Dietetics. However, the research is clear: Substituting polyunsaturated fats for saturated fats has made us fatter and sicker.