Expert Panel: Omega-6 Won't Hurt Heart

The American Heart Association (AHA) has come to the
defense of omega-6 fatty acids, the fats found in many grains and most
vegetable oils that some have linked to heart disease.

In a scientific advisory released today, an AHA panel noted that there is
little credible evidence that omega-6 fatty acids promote inflammation and
increase cardiovascular risk.

The experts concluded that reducing omega-6 polyunsaturated fatty acids
(PUFAs) from their current levels would be more likely to increase the typical
American's risk for heart disease than decrease it.

"Our goal was simply to let Americans know that foods containing omega-6
fatty acids can be part of a healthy diet, and can even help improve your
cardiovascular risk profile," researcher and panel chairman William S.
Harris, PhD, notes in a news release.

Good Fat, Bad Fat?

Harris tells WebMD that the advisory was issued to clear up confusion about
omega-6, which has been cast as a dietary villain by some in the nutrition
community.

Barry Sears, PhD, who created the Zone Diet, is the most well-known
proponent of the idea that dietary omega-6 fatty acids promote inflammation and
heart disease.

In his latest book, Sears claims that heart disease and many other chronic
diseases can largely be blamed on the fact that the Western diet contains too
much omega-6 and not enough omega-3, the fat found primarily in salmon and
other fatty fish.

He argues that high-carbohydrate diets that contain high levels of
omega-6-rich grains and vegetable oils promote chronic disease by producing the
inflammatory arachidonic acid (AA).

But Harris says there is no proof that omega-6 from vegetable sources
promotes inflammation and plenty of evidence that eating grains and vegetable
oils protects the heart.

The AHA panel reviewed the scientific evidence examining the impact of
omega-6 PUFAs on the risk of heart and cardiovascular disease.

Their analysis of more than two dozen studies reveals that:

• People in observational studies who ate the most omega-6 fatty acids
  typically had lower rates of heart disease than people who ate the
  least. 


• Patients with heart disease tended to have lower levels of omega-6 in their
  blood than people without the disease. 


• People in controlled trials who ate diets high in omega-6 were less likely
  to develop heart disease than those who ate diets that were low in
  omega-6.

"Although increasing omega-3 PUFA tissue levels does reduce the risk of
chronic heart disease, it does not follow that decreasing omega-6 levels will
do the same," panel members write in the Feb. 17 issue of the AHA journal
Circulation. "Indeed, the evidence considered here suggests that it
would have the opposite effect."

Heart-Healthy Eating

The AHA recommends eating a diet that includes plenty of fruits, vegetables,
high-fiber whole grains, lean meats, poultry, and at least two servings of fish
a week.

The panel recommended that 5% to 10% of calories come from omega-6 fatty
acids, and Harris says most Americans get it about right. The main omega-6
fatty acid obtained from diet is linoleic acid, which mainly comes from
vegetable oils such as safflower, corn, and sunflower.

Instead of focusing on omega-6, Harris says people who want to reduce their
heart disease risk should strive to lower their intake of saturated fats from
fatty and processed meats and increase the omega 3-fatty acids in their diet by
eating fish or taking fish oil supplements.

"Omega-6 fatty acids are not the villains," he says. "These are
good fats that are important for cardiovascular health."

AHA past president Robert Eckel, MD, agrees that the aalysis does not
support the claim that omega-6 PUFAs promote inflammation. Eckel is a professor
of medicine at the University of Colorado in Denver.

"The evidence is overwhelming to indicate that diets higher in vegetable
oils and lower in saturated fats and trans fats are heart healthy," he
tells WebMD. "This needs to be emphasized to counter recent claims that
eating vegetable oils is harmful."

By Salynn Boyles
Reviewed by Louise Chang
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