Coronary heart disease (CHD) risk is positively linked with dietary saturates and negatively linked with polyunsaturated fatty acids (PUFAs). Consumption of omega-3 fatty acids, such as in fish, appears highly protective against CHD. PUFAs (linoleic acid or omega-6) lower low-density lipoprotein (LDL) cholesterol levels most, and saturates, especially butter fat, raise LDL levels most. Fish oil fatty acids (omega-3) lower triglyceride and raise high-density lipoprotein (HDL) cholesterol levels.

A higher ratio of dietary omega-3 to omega-6 fatty acids than is currently consumed in our population may be desirable, and can be achieved by increasing consumption of fish and alpha-linolenic acid in canola, soy and flaxseed oils. Large prospective trials show that people who experience least CHD have a pattern of eating that is rich in fish, PUFAs, whole-grain cereals, fruits and vegetables and low-fat dairy foods, and low in saturates from dairy fat, meat fat and fried foods.