The so-called Mediterranean dietary pattern has long been associated with lower rates of many chronic diseases such as heart and cardiovascular disease, diabetes, over-weight and obesity and more.
The diet tends to be rich in fruits, vegetables, whole grains, nuts, seeds, fish and seafood, and pulses [chickpeas, lentils, dried peas and beans] which offer a lot of nutrients, nutrients that are often lacking in optimal amounts in North American diets, as well as, being rich in the usual health promoting suspects such as anti-oxidants and phyto-nutrients; but there’s likely much more to the story.
A new study offers novel insight into the Mediterranean diet and health
The Story: Scientists have discovered a novel way in which the long promoted Mediterranean diet may prevent stroke in a way that has nothing to do with the nutrients per se according to a new study that appeared in the August 2013 issue of the journal Diabetes Care. All foods interact with, and influence, the activity of our genes; packages of information which direct countless bodily activities such as turning on disease-fighting genes and turning off disease-promoting genes. Genes also influence the production of enzymes, special proteins that influence metabolism (as in biological activity/reactions that help ‘run’ the body). In turn, our unique genetic make up influences how each of us respond differently to the foods, and nutrients, that we eat.
In this study, researchers looked at how the Mediterranean diet interacted with a specific gene whose activity is involved with type 2 diabetes.
The study involved over 7000 men and women involved in the Prevencion con Dieta Mediterranean (PREDIMED) trial, carried out over a 5-year period to see whether a Mediterranean, or a low-fat controlled diet, had an effect on the risk for cardiovascular disease, stroke, heart attack, diabetes and whether genetics play a part in their development.
Genes load the gun but environment pulls the trigger
Turns out that those who carried two copies of the gene in question, for the science geeks, specifically Transcription Factor 7-like 2 (TCF7L2), who also followed a Mediterranean style diet saw a reduced number of strokes; normally having two copies of the gene would be expected to increase the risk for stroke which is exactly what was found in the low-fat diet group. The low-fat diet group had three times the stroke risk compared to the Mediterranean diet group; the authors state:
“the Mediterranean diet (an environmental factor) was able to eliminate any increased genetic susceptibility, putting those participants on an even playing field with people with only one or no copies of the gene variant”
Interestingly, there wasn’t any difference in fasting blood sugar, total blood cholesterol, LDL cholesterol, or triglyceride levels between those with gene variant and those without; the diet offered protection against stroke by ‘over riding’ the susceptible genes that had nothing to do with traditional risk factors.
This is the idea behind the concept of epigenetics where environmental factors (anything outside of the body like food, beverages, exposure to virus, pollution etc) positively or negatively influence health. It’s estimated that only about 5% of our genes directly influence health, the other 95% of risk is under our control to a large degree – this is a good news story.
Regardless of one’s genetic make-up, the Mediterranean-style of eating/diet continues to be beneficial for everyone, and anyone can benefit from following the main tenants including olive oil (other oils are likely equally beneficial such as macadamia nut or avocado oil), more plant-based foods like whole fruits, vegetables, whole and intact grains, pulses, nuts and seeds, more fish and seafood, fresh and dried herbs. While we’re add it, small amounts of red wine, in moderation (4 or so standard glasses – 5 oz or 150 ml – per week) can also be an option; the data is clear on this but it’s not necessary to include it in order to reap the benefits of this nutritious dietary pattern.
The study can be found here: Mediterranean Diet Reduces the Adverse Effect of the TCF7L2-rs7903146 Polymorphism on Cardiovascular Risk Factors and Stroke Incidence. A randomized controlled trial in a high-cardiovascular-risk population