Blood vessels appear healthier after people consume olive oil high in phenolic compounds

C.Health · medicine forum addict Joined: 04 Sep 2005 Posts: 63

http://www.medicalnewstoday.com/medicalnews.php?newsid=33381#
Blood vessels appear healthier after people consume olive oil high in
phenolic compounds
11 Nov 2005

Phenolic compounds in olive oil, which have antioxidant, anti-inflammatory
and anti-clotting properties, may explain cardiovascular health benefits
associated with the so-called Mediterranean Diet, according to a new study
in the Nov. 15, 2005, issue of the Journal of the American College of
Cardiology.

"It could be that the beneficial effect of the Mediterranean diet on
cardiovascular disease and arteriosclerosis depends on the synergistic
effects of the different nutrients that constitute complete foods and, as an
example, virgin olive oil is more than fat because it is a real juice with
other healthy micronutrients," said Francisco Pérez Jiménez, M.D., Ph.D.,
from the Reina Sofia University Hospital in Córdoba, Spain.

The researchers, including lead author Juan Ruano, M.D., Ph.D., fed
breakfasts including olive oil (that was either high or low in phenolic
content) to 21 study participants (5 men, 16 women) who had high cholesterol
levels, but were otherwise apparently healthy. The functioning of the
endothelium (the inner lining) of small blood vessels of the fingers
(instead of "in the arms") of participants and the concentrations of certain
components in blood serum, including nitric oxide, improved after the
polyphenol-rich breakfast.

"This is the first study that shows a direct benefit of an olive oil with
high content in phenolic compounds on endothelial function in vivo," Dr.
Pérez Jiménez said.

After fasting overnight, the participants reported to the hospital, where
they ate a breakfast of 60 grams of white bread with 40 milliliters of
virgin olive oil, a relatively high-fat meal. The meals also included
vitamin A supplementation. Over the next four hours, blood samples were
taken and the researchers used Doppler laser to measure endothelial
responses to sudden changes in blood flow, which were produced by inflating
and then deflating a blood pressure cuff. The response is known as ischemic
reactive hyperemia. Poor responsiveness to this sort of blood flow test is
considered an early warning sign of cardiovascular disease. Previous studies
have linked high-fat meals to poor endothelial function lasting for several
hours after eating.

In order to focus on the role of phenolic compounds, the researchers put
each participant through the process twice in a randomized order, once using
olive oil naturally high in phenolic compounds (400 parts per million) and
once with the same brand of olive oil that had been processed to remove most
of the phenolic compounds (80 parts per million remaining).

"We think, looking at our results, that the reduction in oxidative stress
and the increase in the nitric oxide bioavailability are behind the observed
improvement in ischemic reactive hyperemia," Dr. Pérez Jiménez said.

Dr. Pérez Jiménez said that olive oil may be superior to seed oils because
it is a natural juice, pressed from the olives, so it does not go through
the type of processing needed to extract oil from seeds, such as sunflowers,
soybeans and rapeseeds. Nevertheless, he said further studies should be done
to investigate whether phenolic compounds in olive oil can be linked to
improved health outcomes.

"Although our study shows a direct benefit of an olive oil with high content
in phenolic compounds on endothelial function in humans, carefully
controlled studies in appropriate populations, or with a large sample size,
are required to definitively establish the in vivo antioxidant properties of
these components in relation to cardiovascular disease outcomes. On the
other hand, some data suggest that endothelial dysfunction could be a
surrogate end point for prediction of cardiovascular risk, but we need more
information on the utility of the different methods to evaluate endothelial
dysfunction," Dr. Pérez Jiménez said.

Robert F. Wilson, M.D., from the University of Minnesota in Minneapolis, who
was not connected with this study, noted that health benefits of a
Mediterranean diet were described over 50 years ago.

"This study demonstrates one possible mechanism by which olive oil rich in
phenolic substances improves the functioning of the circulation. The authors
found that after test subjects took olive oil spiked with phenolic
compounds, their blood vessels could dilate better, which could improve
blood flow. These findings are particularly interesting because similar
studies after high fat meals, like a burger and fries, showed impairment of
normal blood vessel functions," Dr. Wilson said.

Dr. Wilson pointed out that not all olive oils have a high phenolic content.

"So these results might not be true for all olive oil on the shelf at the
grocery store," he said.

Juan J. Badimon, Ph.D., F.A.C.C., from the Mount Sinai School of Medicine in
New York, New York, who also was not connected with this study, said it was
well-designed and will help address controversy about whether olive oil
benefits or impairs blood vessel health.

"One of the beauties of this study is that using a randomized, sequential,
crossover study, so that the same patients were exposed to the same oil,
once with low phenolic content and the other with high phenolic content, the
only variable in this study is the phenolic content of the olive oil," Dr.
Badimon noted. "These results indicate that a very small change in diet,
like using olive oil with a high phenolic content may have a significant
impact in the progression of atherosclerosis."

Disclosure Box

This study was supported by the Spanish Plan for R&D (SAF 03/05770 to Dr.
Pérez-Jiménez), Plan Andaluz de Investigación (to Dr. Lopez-Miranda and Dr.
Pérez-Jiménez), Diputación Provincial ( Córdoba), Denomination of Origin
Boards of Baena and Priego de Córdoba, and Cultural Foundation "Reina
Sofia-Cajasur."

Amy Murphy
amurphy@acc.org
American College of Cardiology
http://www.acc.org

montygram · medicine forum Guru Joined: 30 Apr 2005 Posts: 825

What most of these studies show is that olive oil is better than stuff
like safflower oil, but olive oil can vary greatly in quality. Some of
it is very bad, and it's very difficult to tell. And even if it's the
highest quality, how are you going to cook with it? Do you want to eat
it raw? Fresh coconut oil is best - you can taste the freshness in it.
In Bruce Fife's book, Coconut Cures, he has a chart showing that the
"heart healthiest" people are those who consume the most coconut, not
those on the "Med Diet." It's not even close.

Enrico C · medicine forum Guru Joined: 18 May 2005 Posts: 558

On 12 Nov 2005 20:27:19 -0800, montygram wrote in
<news:1131856039.005825.305370@f14g2000cwb.googlegroups.com> on
misc.health.alternative,sci.med.nutrition,sci.med :

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