Submitted to: Getreide Mehl Und Brot
Publication Type: Review Article
Publication Acceptance Date: September 30, 2003
Publication Date: September 30, 2003
Citation: Kahlon, T.S. 2003. Cholesterol lowering with grain fractions. Getreide Mehl Und Brot. Vol 57: 279-291. Interpretive Summary: This manuscript reviews animal and human studies showing cholesterol lowering by oat bran, rice bran and barley fractions. Cholesterol lowering activity is present in soluble fiber, sterol fraction as well in other components. Possible mechanisms for this action include increased excretion of fat, cholesterol and bile acids, and inhibition of rate limiting enzymes for cholesterol and bile acid synthesis. Population studies have shown that for 1% reduction in plasma cholesterol there is 2-4% reduction in the risk of heart disease and stroke. In normocholesterolemic subjects, although the effect of cereal dietary fiber on plasma lipids and lipoproteins is small, these changes would have a significant potential for reducing cardiovascular risk for the whole population.
Technical Abstract: Animal and human studies suggest that oat bran, rice bran and barley fractions lower cholesterol. In oats, active components appear to include B-glucans, soluble fiber and phytosterols. Possible mechanisms for this activity included increased fecal cholesterol and bile acid excretion, increased GI tract length and increased production of short chain fatty acids. In rice bran, cholesterol-lowering activity is associated with unsaponifiable matter of oil as well as other components. Proposed mechanisms of cholesterol-lowering by rice bran include an increased fecal excretion of fat, cholesterol and bile acids. Hypocholesterolemic effects of barley fractions appear to be due to its soluble B-glucans, tocotrienols and other components. Possible mechanisms for cholesterol-lowering by barley are increased fecal fat and bile acid excretion, and inhibition of HMG-CoA reductase and 7-alpha-hydroxylase, the rate-limiting enzymes for cholesterol and bile acid synthesis.