Researchers at the University of Queensland in Brisbane have identified a new mechanism for how cereal such as oats reduce the amount of cholesterol in the blood stream. The discovery may lead to ways of boosting cholesterol-fighting properties of other cereals, including wheat.
“We’ve known for some time that beta-glucans in oats reduce blood cholesterol, but now we’ve discovered one of the ways in which they do it,” said Mike Gidley, Ph.D., director for the Centre for Nutrition and Food Sciences at the University of Queensland.
Using pigs as a model for humans, the researchers found beta-glucan in oats reduced the amount of circulating bile that is secreted during digestion. Beta-glucans added to the diets of the pigs for 26 days led to decreases of 24% in blood total bile acids, 34% in total cholesterol and 57% in L.D.L. cholesterol.
“We aren’t quite sure yet why, but in the presence of beta-glucan there is much less circulating bile,” said Purnima Gunness, Ph.D., lead researcher. “This means that fats, which bile helps break down, are not digested as rapidly or completely.”
Beta-glucans are soluble fibers that naturally occur in the cell walls of some plants, particularly cereals.
“Now that we know how beta-glucans positively impact cholesterol levels, it will help us identify other fibers in plant cell walls that may have a similar effect,” Dr. Gunness said.
The study appeared in the December issue of The FASEB Journal, the official journal of the Federation of American Societies for Experimental Biology.