NEW YORK - When it comes to heart health, virgin
olive oil may have an edge over other vegetable fats, new research suggests.
Reporting in the Annals of Internal Medicine, European researchers say virgin
olive oil may be particularly effective at lowering heart disease risk because
of its high level of antioxidant plant compounds.
In a study of 200 healthy men, the researchers found that virgin olive oil -
rich in antioxidants called polyphenols - showed stronger heart-health effects
than the more extensively processed "non-virgin" variety.
The findings suggest that virgin olive oil has more going for it than its
supply of heart-healthy monounsaturated fat, according to the study authors.
Polyphenols, they say, may account for some of the health benefits that have
been attributed to the oil.
In fact, virgin olive oil is the only vegetable oil that's rich in
polyphenols, Dr. Maria-Isabel Covas, the study's lead researcher, told Reuters
Health.
"All vegetable oils other than virgin olive oil are submitted to a (refining)
process in which polyphenols are practically lost," explained Covas, a
researcher at the Municipal Institute for Medical Research in Barcelona, Spain.
Even "ordinary" olive oil has a lower polyphenol content, she noted, because
it's a mixture of virgin olive oil and a more-processed form of the oil.
For their study, Covas and her colleagues had 200 young and middle-aged men
use each of three olive oils for three weeks apiece. One oil was a virgin olive
oil high in polyphenols; the other two were more heavily processed varieties
with moderate to low polyphenol levels.
The men used the oils in place of other dietary fats.
At the end of the study, the researchers found that the men's levels of
"good" HDL cholesterol were highest after their three weeks on virgin olive oil.
They also showed a greater decline in markers of so-called oxidative stress -- a
process that helps deposit particles of "bad" LDL cholesterol on the artery
walls and can lead to a hardening and narrowing of the vessels supplying the
heart.
Monounsaturated fat is well known to be a healthier alternative to the
saturated fat found in animal products like butter, Covas noted. That fact,
along with the benefits of polyphenols, she said, make olive oil "a good source
of fat."
But she stopped short of recommending virgin olive oil as a replacement for
other vegetable oils, saying large clinical trials are needed to see whether
there's a health advantage.
SOURCE: Annals of Internal Medicine, September 5, 2006.
