Soy Protein Diet Cuts Cholesterol, Study Finds

Eating tofu and other soybean products can significantly reduce cholesterol levels, scientists said Wednesday.

Six weeks to three months of substituting soybeans for animal proteins cut total blood cholesterol by an average of 9.3%, a University of Kentucky team reports in today’s issue of the New England Journal of Medicine.

The researchers analyzed 38 previous clinical studies with a total of 740 subjects, going back 18 years.

The soybean diets were most effective in people who had high cholesterol levels to start with, the researchers said. Subjects’ levels of LDL, or “bad” cholesterol, dropped an average of 12.9%, while levels of HDL--”good” cholesterol--rose slightly.

“This is the bottom line: Increased intake of soy equals decreased risk of coronary heart disease,” said Dr. James Anderson, lead author of the paper, at a news conference Wednesday.

But he and his colleagues conceded that their study did not consider whether substituting other vegetable proteins or simply reducing animal protein would produce the same benefits. He said he received $5,000 from Protein Technologies International, which makes soy protein, to help pay for the work.

Soy cuts cholesterol about as much as low-fat diets do, according to Margaret Cook-Newell, a co-author of the study.

Cook-Newell said the American Heart Assn.’s diet can reduce cholesterol by 5% to 10%; a very low-fat, high-fiber diet can reduce levels 13% to 19%; and drugs can lower levels 10% to 20%.