The Results
Individuals were followed up for an average of 4.5 years and only 275 of the 1,393 individuals developed MCI. The study did show that individuals who had the strongest adherence to the Mediterranean diet had the lowest risk of developing MCI.
How the Mediterranean diet lowers the risk of cognitive impairment is not fully understood but there is strong evidence relating the Mediterranean diet to a lower risk for vascular risk factors, such as high fats (e.g. cholesterol), hypertension and heart disease.
In addition, there is good evidence that shows strong adherence to a Mediterranean diet can also improve carbohydrate breakdown and profoundly decrease plasma glucose levels, serum insulin levels and insulin resistance, which may partly explain its beneficial effects on lowering incidence of MCI.
Alternatively, the protective effect of the Mediterranean diet on MCI may be mediated by some antioxidant effect or may be related to one particular food component in the diet.
Conclusion
These are preliminary data and the findings have not been replicated in a randomized controlled trial. In any case, eating a good, healthy diet consisting of vegetables, sea food, whole grains, fruits and a glass of wine on a regular basis is not only good for the brain but for the entire body.
http://www.medscape.com/viewarticle/588276