Physical activity and the Mediterranean diet: food for thought

“What’s good for the heart is good for the brain!” a speaker at a conference once said. He was referring to dietary and lifestyle change for stroke prevention.

The Mediterranean diet has been associated with lower risk for cardiovascular and cancer death and longer survival. Until recently, the data for prevention of dementia has been less clear. A study published in the Journal of the American Medical Association (JAMA. 2009;302(6):638-648) found that individuals with higher adherence to the Mediterranean diet had lower rates of cognitive decline.

Another study in the same issue (JAMA. 2009;302(6):627-637) found that higher adherence to routine physical activity and Mediterranean diet were both associated with reduced risk for Alzheimer’s dementia. High physical activity was defined as 1.3 hours of vigorous physical activity per week, 2.4 hours of moderate physical activity per week, four hours of light physical activity per week or any combination. Compared with those who had no physical activity, individuals reporting much physical activity had a 33% to 48% lower risk for Alzheimer’s dementia. Those in the highest tertile of adherence to the Mediterranean diet had a 32% to 40% lower risk.

Of course, association does not prove causation. It is possible that physical activity is only a marker for those at lower risk due to other reasons. Dementia may develop over years or decades before it is clinically evident. Those with lower functional status may not be as physically active. Adherence to a specific diet could be as much a marker for other healthy behaviors or socioeconomic status as it might be an independent explanation for reduced risk.

I recommend routine physical activity and dietary modification to all patients at increased cardiovascular risk. Among the dietary choices available, the Mediterranean diet is one option out of several for which there is evidence to suggest benefit.

For many patients, however, there are misconceptions regarding the exact definition of the Mediterranean diet. It is not gorging on pasta at your local Italian restaurant or eating a large pizza. The Mediterranean diet consists of high intake of plant foods such as legumes, fruits, vegetables and grains, moderate intake of fish and low to moderate intake of dairy products, red meat and poultry. Intake of saturated fat is low with consumption of olive oil as the primary source of monounsaturated fat. Wine is consumed in low to moderate amounts, usually with meals. The Mediterranean lifestyle also includes moderate physical activity.

For patients seeking more specific information, the Mayo Clinic has an excellent summary at: http://www.mayoclinic.com/health/mediterranean-diet/CL00011

Another useful source is WebMD: http://www.webmd.com/diet/features/the-mediterranean-diet