Hold The Oat Bran

Well-intentioned as it may be, the A.H.A. is stepping into a quagmire by trying to serve as a dietary oracle. Too often scientific ground shifts, and today's notion of sound nutritional advice becomes tomorrow's myth. The latest case in point: oat bran. Two years ago, the high-fiber grain was elevated to alimentary sainthood after a few studies showed that people who ate a diet rich in the stuff enjoyed a significant drop in their cholesterol levels. Doctors began recommending the grain to patients, and food manufacturers rushed to add it to everything from muffins to tortilla chips.

Last week the halo slipped. According to a report in the New England Journal of Medicine, oat bran has no special power to reduce cholesterol levels. In fact, it works no better than low-fiber grains and causes more bloating and diarrhea than some. In a study performed at the Brigham and Women's Hospital in Boston, Dr. Frank Sacks and colleagues randomly switched 20 healthy men and women between two six-week diets: one contained 100 grams of oat bran daily, the other 100 grams of low-fiber wheat. Cholesterol levels dropped an average 7.5% -- no matter the diet. The simple explanation: both grains work indirectly by displacing other items in the diet. People who fill up on oat bran or wheat have less room for scrambled eggs, chocolate cake and other fatty delectables.