Eat like you live along the Mediterranean and you could reduce your risk of having a stroke â?? even if the risk is genetic!
Research has found that Mediterranean diet interacts with the gene variant strongly associated with development of type 2 diabetes and helps prevent strokes.
This is according to a report from Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University and from the CIBER FisiopatologÃa de la Obesidad y Nutricion in Spain.
Published online in Diabetes Care, the report is significant advance for nutrigenomics, the study of the linkages between nutrition and gene function and their impact on human health.
The Mediterranean menu
According to the Mayo Clinic, the Mediterranean diet consists of…
Fruits and vegetables
Whole grains and legumes
Fish and poultry is eaten at least twice a week
Red meat is limited to no more than a few times a month
Healthy fats like olive oil instead of butter
Herbs and spices used to flavour food instead of salt
Studying the benefits of the Mediterranean diet
The researchers set out to investigate whether genetics contribute to the cardiovascular benefits seen in the Prevencion con Dieta Mediterranea (PREDIMED) trial. Based in Spain, the randomised, controlled trial enrolled more than 7,000 men and women assigned to either a Mediterranean or low fat control diet and monitored them for cardiovascular disease, stroke and heart attack for almost five years.
“Our study is the first to identify a gene-diet interaction affecting stroke in a nutrition intervention trial carried out over a number of years in thousands of men and women,” said senior author JosÃ© M. OrdovÃ¡s, Ph.D., director of the Nutrition and Genomics Laboratory at the USDA HNRCA at Tufts University.
“The PREDIMED study design provides us with stronger results than we have ever had before. With the ability to analyse the relationship between diet, genetics and life-threatening cardiac events, we can begin to think seriously about developing genetic tests to identify people who may reduce their risk for chronic disease, or even prevent it, by making meaningful changes to the way they eat.”
Led by OrdovÃ¡s and corresponding author Dolores Corella, Ph.D., of the CIBER Fisiopatologia de la Obesidad y Nutrici?n , the researchers focused on a variant in the Transcription Factor 7-Like 2 (TCF7L2) gene, which has been implicated in glucose metabolism but its relationship to cardiovascular disease risk has been uncertain. About 14 percent of the PREDIMED participants were homozygous carriers, meaning they carried two copies of the gene variant and had an increased risk of disease.
The Mediterranean diet found to be better than a low-fat diet
“Being on the Mediterranean diet reduced the number of strokes in people with two copies of the variant. The food they ate appeared to eliminate any increased stroke susceptibility, putting put them on an even playing field with people with one or no copies of the variant,” explained OrdovÃ¡s, who is also a professor at the Friedman School of Nutrition Science and Policy at Tufts University.
“The results were quite different in the control group following the low fat control diet, where homozygous carriers were almost three times as likely to have a stroke compared to people with one or no copies of the gene variant.”
To find out how closely the PREDIMED participants adhered to the Mediterranean diet prior to the trial, the authors examined food frequency questionnaires.
“Again, we saw that the Mediterranean diet appeared to compensate for genetic influence,” said Corella, who is also a scientist in the Genetic and Molecular Epidemiology Unit at the University of Valencia.
“If adherence to the diet was high, having two copies of the gene variant had no significant influence on fasting glucose levels. The same was true or three common measures of cardiovascular disease risk: total blood cholesterol, low density lipoprotein and triglycerides. Conversely, these risk factors were considerably higher in homozygous carriers with low adherence to the diet.”
The results of the study were not significantly changed by adjusting for variables that could have affected the findings, including type 2 diabetes, body mass index (BMI), and heart and diabetes medications.
The researchers note more studies are needed to determine what mechanism may be involved in the interaction they observed. They also intend to continue to mine the PREDIMED data for other gene diet interactions that may be associated with stroke as well as heart attacks.
Recommended reading: What are the early warning signs of a stroke?