Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Phenolic compounds may explain Mediterranean diet benefits

10.11.2005


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



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."

Amy Murphy | EurekAlert!
Further information:
http://www.acc.org

More articles from Health and Medicine:

nachricht Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital

nachricht New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>