The hypocholesterolemic effects of beta-glucan in oatmeal and oat bran: a dose-controlled study

High blood levels of cholesterol (hypercholesterolemia) affect one in four adults in the United States and are considered a risk factor for the development of coronary artery disease. Dietary modification to reduce fat intake is the first step in lowering cholesterol levels, but other aspects of the diet are also under investigation for fat-reducing effects. Water-soluble fibers, such as those found in fruits, dried beans, legumes, barley, psyllium and oats, may lower fats and cholesterol in the blood. Oat cereals rich in beta-glucan are a potential dietary therapy for high cholesterol levels. To test how well oatmeal and oat bran lowered cholesterol, 148 adults with elevated levels of low-density lipoprotein cholesterol (LDL-C) completed a study during which they were given either one, two, or three ounces of oatmeal meal or oat bran, or one ounce of farina each day for 12 weeks. Beta-glucan, the water-soluble fiber in oat cereals, lowered cholesterol levels when taken in conjunction with a low-fat diet. Two ounces of oat bran lowered cholesterol better than one ounce, but three ounces did not produce a greater reduction. (This observation may be related to the small size of the study.) Three ounces of oatmeal were needed to reduce cholesterol as much as two ounces of oat bran. Theories about how soluble fiber reduces cholesterol are reviewed. It is also possible that the cholesterol-lowering effect is not related to beta-glucan, but to the effects of a compound with vitamin E activity or the amino acid content of oats, especially the arginine-lysine ratio. (Consumer Summary produced by Reliance Medical Information, Inc.)