| WEDNESDAY, May 21 (HealthScoutNews)
-- Taking capsules containing fruit and vegetable concentrates could
lessen damage to arteries caused by a high-fat meal, a new study suggests.
The study, published in the May 21 issue of the Journal of the American
College of Cardiology, focused on three dozen volunteers, each of whom ate
a 900-calorie McDonald's meal containing 50 grams of fat: an Egg McMuffin,
a Sausage McMuffin, two hash browns and a non-caffeinated drink.
"I think it sort of confirms what people have known for a while -- that
is, eating fruits and vegetables long-term is beneficial in decreasing the
risk of cardiovascular disease," says study co-author Dr. Gary D. Plotnick,
a professor of medicine at the University of Maryland School of Medicine.
Plotnick cautions, however, that the study results are preliminary and
need to be confirmed by a much larger study. And he warns against assuming
you can take a capsule concentrate containing fruit and vegetables, then
eat high-fat meals without worry.
"What I don't want to get across is you can take pills and eat anything
you want because there are detrimental effects of high-fat meals
independent of what we looked at," he says. For example, Plotnick says,
the study did not examine the high-fat meal's effect on cholesterol.
Before the meal, researchers divided the volunteers into three groups. For
four weeks, one group received the capsule concentrate; one group, the
capsule concentrate and an herbal supplement; the third group, a placebo.
The fruit-and-vegetable supplements appeared to help arteries retain much
of their ability to expand in response to a sudden increase in blood flow,
the study found.
Among those who took only placebos, however, the high-fat meal
significantly reduced the blood vessels' ability to expand with an
increase in blood flow. (Addition of the herbal supplement had no
significant effect on the vessels.)
The researchers measured blood vessel response three hours after the meal
by using a blood-pressure cuff to stop blood flow in the arm for five
minutes, then releasing the cuff, causing a sudden surge in blood flow.
After a high-fat meal, the inner lining of blood vessels -- called the
endothelium -- does not expand as well in response to an increase in blood
flow because the endothelium doesn't release as much nitric oxide,
Plotnick says.
The researchers received support for the study from Natural Alternatives
International, the manufacturer of the fruit-and-vegetable capsules used
in the research.
The researchers suggest the antioxidants in fruits and vegetables may have
helped endothelium function among those who took the concentrate.
Diminished function of the endothelium can be an early sign of
atherosclerosis, the gradual blocking of arteries that can lead to heart
attack and stroke, the study says.
Researchers not involved in the study say they wouldn't read too much into
its results.
In an editorial in the journal accompanying the study, Dr. Jane E.
Freedman, associate professor of medicine at Boston University School of
Medicine, says the study presents a possible reason for protective
benefits of compounds in fruits and vegetables. But, she writes, further
research is needed to determine the possible benefits of the
fruit-and-vegetable concentrate.
"This is a very limited study that should not be over-interpreted,"
Freedman says.
She also says the study results can't be extended to other fatty foods,
and adds that endothelium function has not been proved to correlate with
cardiovascular disease.
Alice H. Lichtenstein, a professor of nutrition, science and policy at
Tufts University School of Medicine, points out that ingredients in the
concentrate -- but not found in fruits and vegetables -- could have
affected the study's outcome.
Lichtenstein, vice chairwoman of the American Heart Association Nutrition
Committee, says the study focused on a "very narrow question asked under
very controlled and extreme experimental conditions."
"It would be premature to make a recommendation based on this study," she
says.
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