Study Links Steric Acid With Heart Disease
Dec. 23, 1999 (Atlanta) -- Steric acid, traditionally thought to be a benign saturated fat, is just as harmful as other saturated fats in developing heart disease, according to a report in the December issue of the American Journal of Clinical Nutrition. Experts now urge dietary reduction of all saturated fats to help prevent coronary heart disease (CHD).
Researchers reviewed the medical histories and lifestyle characteristics of over 80,000 middle-aged women enrolled in the Nurses' Health Study from 1976 to 1990. The study focused primarily on the diets of healthy women who later developed CHD.
The data showed that red meat and high-fat dairy products increased the risk of CHD, whereas poultry, fish, and low-fat dairy products decreased the risk. The chief investigator urges dietary reduction of all saturated fats and says foods high in steric acid are no exception.
"Steric acid is a type of saturated fatty acid that's been very controversial," says Frank Hu, MD, PhD, an assistant professor of nutrition at Harvard University. "It's been thought that steric acid may be neutral in terms of CHD risk. But the Nurses' data shows it's just as harmful as other saturated fats." The importance of this finding was acknowledged in a corresponding editorial.
"The Nurses' Study has helped clarify the ... role of steric acid in CHD," says William Connor, MD, director of the lipid atherosclerosis laboratory and professor of medicine at the University of Oregon. "We still don't know exactly how steric acid increases the risk of CHD, but we do know it depresses high-density lipoprotein [HDL], also known as good cholesterol." As a chocolate lover, Connor reluctantly urges restraint.
"For a long time, many believed that the fat in chocolate was benign. But now we know its steric acid content puts it in the same category as meat and butter. And unfortunately, this means that chocolate should be savored on special occasions only," says Connor. Dieticians offer similar advice for reducing dietary intake of animal fat.
"Rather than eliminating red meat like beef and pork, we urge patients to decrease portions and increase variety," says Cindy Moore, MS, RD, director of nutritional therapy at the Cleveland Clinic and spokesperson for the American Dietetic Association. "Lean cuts are best and portions should be about the size of a computer mouse. It's also important to get protein from low-fat sources like poultry, fish, or soy." Moore says reducing dairy fat is even easier.