Mediterranean Diet and Physical Activity May Lower Risk of Alzheimer's Disease
Dr. Féart’s group offered possible explanations as to why some of their findings differed from those of Dr. Scarmeas and colleagues. “First, the length of follow-up differed (range, 0.2 to 13.9 years or 0.9 to 16.4 years in US studies vs 1.6 to 6.1 years in the [French] cohort),” stated Dr. Féart and coauthors, which included Dr. Scarmeas. The results suggest a “beneficial effect of the Mediterranean diet during the prodromal phase of dementia rather than in the very last years preceding dementia,” reported the authors. “Second, country-specific characteristics of the dietary patterns may partly explain the discrepancies observed between the French and US studies, despite similar mean Mediterranean diet scores. For instance, French individuals tend to eat fruits and vegetables more often than individuals in the United States.” Therefore, noted Dr. Féart, some overlap could occur. “The low French consumers may be high US consumers,” leading to a decreased chanced to observe an association between diet and cognitive decline or incidence of dementia, she said.
“The Mediterranean diet pattern probably does not fully explain the better health of persons who adhere to it, but it may contribute directly,” Dr. Féart and colleagues concluded. “A Mediterranean diet also may indirectly constitute an indicator of a complex set of favorable social and lifestyle factors that contribute to better health.”
Food for Thought
In an accompanying editorial, David S. Knopman, MD, of the Department of Neurology, Mayo Clinic in Rochester, Minnesota, said that the two studies provide “moderately compelling evidence” that adherence to a Mediterranean diet is linked to less late-life cognitive impairment. “The scientific value of these studies cannot be disputed, but whether and how they can or should be translated into recommendations for the public is the question,” he stated. “For now, it is reasonable to nibble on these findings and savor them, but not to swallow them whole.”
