The Influence of Diet on Fecal Lipids in South African White and Bantu Prisoners

Abstract

The influence of dietary fat on stool excretion patterns appears to be more dependent on the nature of the fat component than on the actual amount of fat present in the diet. The effects appear to be significant only in relation to the excretion of bile acids and sterols since stool wet weight and fatty acid excretion were virtually unaffected either by the change from 15 to 40 per cent fat calories, or by different fats (butter, hydrogenated or natural sunflower seed oil) at the higher calorie level. When the diet contained sunflower seed oil the fecal excretion of sterols and bile acids was significantly greater than that obtained with butter; when the diet contained an equal mixture of the two and hydrogenated sunflower seed oil, the effects were intermediate. These changes inversely reflect those produced simultaneously on serum total cholesterol levels. Throughout a particular diet serum cholesterol levels and fecal excretion of sterols and bile acids remained constant; they varied only when the dietary components were altered. Stool excretion patterns were also significantly influenced by the amount of fiber present in the diet. Increasing the fiber content of the diet produced bulkier stools which contained appreciably greater amounts of fatty acids, bile acids and sterols. Decreasing the dietary fiber content produced the opposite effects.