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
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
"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.
"Today, there are lots of low-fat and fat-free dairy products like milk,
cheese, and yogurt. We tell patients to just buy the ones they like the best,
because calcium is so important for healthy bones and teeth. The key is to
develop a realistic plan that patients can actually live with." Moore says
eating in restaurants can sabotage these principles.
"Restaurant portions are completely out of scale with the daily portions
recommended by the ... food guide pyramid. So we recommend splitting an entrée
or taking half of it home," says Moore.
The study was supported by research and nutrition training grants from the
National Institutes of Health.
- Eating red meat and high-fat dairy products increases the risk of coronary
heart disease, while a diet of poultry, fish, and low-fat dairy products lowers
- Steric acid, a type of saturated fatty acid, was previously believed to be
harmless with respect to heart disease, but new research shows it is just as
dangerous as other saturated fats.
- Researchers do not know exactly how steric acid works to increase the risk
of heart disease, but they do know that it lowers levels of good