Mediterranean Diet is Good for Brain Health: Or Is It? Inconsistencies Among Studies Make Generalizing Difficult

Nutrition, lifestyle, and diet choices have been implicated as influencing cognitive health of various populations. Specifically,

Photo by Flickr user  Ian MacKenzie (https://www.flickr.com/photos/bravenewtraveler/2275900255/)
Photo by Flickr user Ian MacKenzie (https://www.flickr.com/photos/bravenewtraveler/2275900255/)

research has shown that adherence to the Mediterranean diet is associated with improved cognitive health and brain aging in the elderly population.

A new review in the journal Current Opinion in Clinical Nutrition and Metabolic Care focused on the longitudinal studied published between 2013 and mid-2014 on the effect of diet on cognitive health and brain aging. A total of 6 longitudinal studies and 2 large-scale meta-analyses were performed during this time.

Important Findings:

  • The two meta-analyses indicate that there appears to be an effect of adherence to the Mediterranean diet on cognitive health in the elderly.
    • Adherence to the Mediterranean diet reduces risk of Alzheimer’s.
    • Adherence to the Mediterranean diet reduces risk of cognitive impairment.
  • The six longitudinal studies from the US and Europe show mixed results in the effect of Mediterranean diet adherence and cognitive health benefits.
  • At present, there is a lack of evidence supporting the idea that the Mediterranean diet is an “optimal dietary strategy” for reducing the risk of age-related cognitive health problems.

The results of this review suggest that there are a lot of inconsistencies in results of several recent studies related to adherence to the Mediterranean diet and cognitive health in the elderly. In general, there does seem to be evidence to support the idea that the Mediterranean diet may be beneficial for long-term mental health in some populations,

Photo courtesy of Wikimedia.com. Public domain.
Photo courtesy of Wikimedia.com. Public domain.

however, the inconsistencies make it difficult to generalize across all populations (for example, all elderly).

While some studies may show benefit, differences in experimental design as well as sample size make it very difficult to draw any conclusions on a general population level. Much more research is needed to clear up these discrepancies, and researchers should be more careful when planning experimental design such that reviews of current literature may (or may not!) reveal more interpretable results.

Source:

Feart, C., Samieri, C., and Barberger-Gateau, P. 2015. Mediterranean diet and cognitive health: an update on available knowledge. Current Opinion in Clinical Nutrition and Metabolic Care 18(1): 51-62.