Many health benefits have been ascribed to the Mediterranean diet. Another one has been added by researchers at the University of Athens in Greece and the University of Alabama at Birmingham. They found that the regimen resulted in a reduced risk of mental decline with age. They reported their findings on April 30 in the journal Neurology.
A Mediterranean diet is rich in olive oil, fruits and vegetable, beans, nuts, and fish, while it is low in foods containing saturated fats, like meat and dairy foods. The investigators conducted a study to determine the relationship of greater adherence to Mediterranean diet and likelihood of cognitive impairment. They also evaluated the interaction of race and vascular risk factors. The study group comprised a large group of individuals who lived in the Stroke Belt (a region in Southeastern United States where health officials have found a higher incidence of strokes). The researchers found that in healthy people, those who more closely followed the Mediterranean diet, were less likely to develop a decline in their thinking and memory skills.
The researchers accessed data from individuals enrolled in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study 2003–2007; they excluded people with a history of stroke, impaired cognitive status at baseline, and missing data on Food Frequency Questionnaires (FFQs). Adherence to a Mediterranean diet (scored as 0–9) was computed from FFQs. Cognitive status was evaluated at baseline and annually during an average follow-up period of 4.0 ± 1.5 years using Six-item-Screener.
The investigators identified cognitive impairment in 1,248 (7%) of 17,478 individuals fulfilling the inclusion criteria. Higher adherence to a Mediterranean diet was associated with lower likelihood of cognitive impairment after adjustment for potential confounders including demographic characteristics, environmental factors, vascular risk factors, depressive symptoms, and self-reported health status. No interaction was found between race and association of adherence to a Mediterranean diet with cognitive status. However, they identified a strong interaction of diabetes on the relationship of adherence to a Mediterranean diet with cognitive impairment; high adherence to a Mediterranean diet was associated with a lower likelihood of cognitive impairment in non-diabetic participants but not in diabetic individuals.
The study authors concluded that higher adherence to a Mediterranean diet was associated with a lower likelihood of cognitive impairment independent of potential confounders. This association was moderated by the presence of diabetes.