Long lauded for its heart health benefits, the Mediterranean diet appears to help provide protection for those genetically at risk for stroke, according to a new study.
The Mediterranean diet is inspired by the traditional diets of Greece, southern Italy, and Spain. It is characterized by a high consumption of olive oil, nuts, legumes, unrefined grains, fruits, and vegetables. The primary protein source is fish, and dairy consumption is mostly limited to yogurt and cheese. Wine is consumed in moderation; meat and meat products play a minor role in daily meals.
All food interacts with, and influences the activity of the genetic packets of information directing every facet of our bodily activities. The opposite is also true — our genes influence how we respond to the foods we eat.
Researchers were interested in seeing how the Mediterranean diet might interact with a specific gene (TCF7L2) whose activity increases the risk for type 2 diabetes.
Particularly telling was the fact that those who consistently cheated on the Mediterranean diet did not receive the health benefits.
Prior to the start of the study, participants had genetic testing performed to determine whether they had a genetic trait in common, a gene mutation that increases the risk for type 2 diabetes. About 30 percent of those in the study carried two copies of the mutation, placing them at high risk — genetically speaking — for a stroke.
People with two copies of the gene who stayed with either variety of the Mediterranean diet had blood sugar levels that were lower than those who had the same genetic risk but ate the low-fat diet. The Mediterranean diet erased any genetic discrepancy in stroke risk. But people with two copies of the TCF7L2 mutation who were on a low fat diet had three times the stroke risk of the Mediterranean diet group.
Also telling was the fact that people who consistently cheated on the Mediterranean diet did not get the health benefits.
Jose Ordovas, one of the authors of the study and the director of the Nutrition and Genomics Laboratory at the USDA Human Nutrition Research Center on Aging at Tufts University, believes that elements and antioxidants in the olive oil and nuts may influence expression of the mutant gene, and thus supply the Mediterranean diet's documented health benefits.
Switching to a Mediterranean diet may be a stretch for some people, but incorporating some of the healthy foods in the diet, such as extra-virgin olive oil, nuts, fruits, and vegetables, should be beneficial to those with risk factors for stroke.
The results of this study are significant for the field of nutrigenomics, the study of the effects of food and food components on gene expression and the resulting effects on a person’s health, particularly the risk of chronic disease. This knowledge may one day improve the lives of people everywhere.
The study is published in Diabetes Care.