by Katherine Sacks/MEDILL NEWS SERVICE
The benefits of the heart-healthy Mediterranean lifestyle may be due, in part, to phenol-rich olive oil, a new study reports. The phenols-or micronutrients found in olive oils-repress gene expression linked to inflammation promotion, which in turn could boost the immune system.
“These findings strengthen the relationship between inflammation, obesity and diet and provide evidence at the most basic level of healthy effects derived from virgin olive oil consumption in humans,” said Fransisco Perez-Jimenez, of the University of Cordoba, Spain in the journal BMC Genomics.
The study, published on April 19, focused on 20 patients who presented pro-inflammatory, or inflammation-promoting, symptoms, including high blood pressure and high cholesterol. Study participants avoided all drugs, vitamins and supplements before the study. During the study, the subjects ate a controlled breakfast that included phenol-rich olive oils.Through analysis, the researchers identified 98 different genes when comparing in the intake of phenol-rich olive oil with low-phenol olive oil.
“Our study showed that intake of virgin olive oil based breakfast, which is rich in phenol compounds, is able to repress in vivo expression of several pro-inflammatory genes, thereby switching activity of peripheral blood mononuclear cells to a less deleterious inflammatory profile,” stated researcher Antonio Camargo Garcia, in e-mail.
This may explain the link between those who eat a “Mediterranean diet” and the reduce risk of cardiovascular disease, according to the researchers. The research suggests that diet can, in essence, inhibit genes which are normally pro-inflammatory. Many of these gene are also linked to obesity, type-2 diabetes, and high cholesterol.
These findings aren’t surprising, said Dr. Karen Moncher, a physician in the preventive cardiology program at University of Wisconsin School of Medicine and Public Health in Madison. She said the best way to get heart-healthy benefits is by following eating habits similar to the Mediterranean diet, which previous studies have shown to reduce risks associated with cardiovascular disease and stroke.
“This study shows that it appears that the olive oil and the monounsaturated fats in olive oil are the things that really make a difference,” said Moncher, “but we just don’t know that for sure.”
Although the study finds preliminary ties between olive oil and reduced cardiovascular disease risks, Toby Smithson, registered dietitian and spokeswoman for the American Dietetic Association, points out the small number of participants in the study.
“There were only 20 people. It was a small study,” Smithson said. “I heed caution when the numbers in a study are so small. On the other hand, olive oil doesn’t raise cholesterol, so that’s a good thing.”
Olive oil and other monounsaturated fats tend to be seen as healthy fats and are linked to reducing risks of heart disease across the board. They can be thought of as simple fats- monosaturated fats are made of a chain of fatty acids and carbon acids that have a single bond.
The results of this study may show that olive oil is a key component of the Mediterranean diet, which includes fruits, vegetables, seeds, nuts and fish, all heart healthy choices, according to Smithson.
“Teaspoon for teaspoon it’s the same amount of fat and calories,” said Smithson. “But the type of fat is what’s beneficial about olive oil because it’s a monounsaturated fat.”
But both Smithson and Moncher said to keep moderation in mind in the case of olive oil, and when eating in general.
“The concern is the amount, to make sure it fits into your calorie intake,” said Smithson. “You don’t want obesity to result because of the higher fat content in the diet. It’s the right kind of fat, but again I heed caution with the amount.”
Although the study shows a health link to olive oil, Moncher stressed the importance of adapting an inclusive healthy lifestyle.
“In the Mediterranean diet in general, across the board everybody emphasizes the combination of things seems to make the difference,” said Moncher. “So this may be more grains, more vegetables, more fruits, and it juts goes back to the whole there’s no one miracle food. It’s always a lifestyle change. There’s no miracle food, it’s just a matter of eating well on a daily basis.”