Dietary Carbohydrates and Low Cholesterol Diets: Effects on Serum Lipids of Man

Abstract

1) Current theories regarding dietary fats and cholesterol are inadequate to explain the differences between cholesterol and other lipid levels in the blood of Orientals as compared with Westerners. 2) To test the hypothesis that the source of carbohydrates in the diet of man can affect lipid metabolism a group of six healthy men were fed a diet which simulated that of the Orient. This provided protein from vegetable sources, a low fat intake (from vegetable oils), an absence of cholesterol, and a comparison between sugar or complex carbohydrates as the major source of carbohydrates. 3) As soon as vegetable protein replaced animal protein, serum cholesterol levels decreased markedly and remained low regardless of source of carbohydrate (sugar versus starch) or level of fat (15 versus 45% of calories). 4) Serum triglycerides were very responsive to source of carbohydrates, rising with sucrose and falling with starch. Although the level of fat calories did affect triglyceride levels, the source of carbohydrate was the dominant factor. 5) The mechanism of this carbohydrate effect is not clear, but several possibilities are discussed.