Mediterranean Diet

Nutritional Pearl: How to Reduce the Risk of Dementia, Alzheimer Disease

Timothy S. Harlan, MD
  • I've written previously on the link between poor diet and the risk of dementia or Alzheimer Disease 1,2. Those previous publications suggested, albeit indirectly, that a Mediterranean-style diet has a role to play in protecting the brain from cognitive declinewhether the more common age-related dementia or Alzheimer Disease. But what kind of role?

    The Research

    In a 2021 prospective study of over 16,000 men and women that tracked participants for over 21 years,3 researchers found that compared to those with a low modified Mediterranean diet score, those with a high score were 20% less likely to be diagnosed with some type of dementia. The effects were greater for men, with a 31% lower risk of dementia for those with a high modified Mediterranean diet score as opposed to a 13% lower risk for women.

    The research made use of data gathered for a study known as the European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain Dementia Cohort Study. The participants recruited were aged between 30 and 70 years between 1992 and 1996. They attended in-person interviews with professionals to assess diet, lifestyle, and medical and reproductive history, then underwent a physical exam to measure height, weight, and waist circumference.

    From the dietary interview, the researchers evaluated each participant's usual diet, assigning each participant's diet a modified Mediterranean diet score. Instead of a 1 - 9 point score, the authors expanded the scoring to include levels of intake for each point: instead of scoring 1 for consuming the minimum of, say, fruits and nuts, the authors assessed the relative intake of fruits and nuts across the entire cohort and awarded a score of 2 for those in the highest third of intake, a 1 for those in the middle third of intake, and 0 (zero) for those in the lowest third of intake.

    Thus, instead of a high score being considered 6 - 9 points, a high score in this modified Mediterranean diet score is 11 - 18. A medium score is 7 - 10 points, and a low score is from 0 - 6 points.

    The Results

    Through access to the national medical record, the authors were able to identify those participants who were diagnosed with dementia (non-Alzheimer type) or dementia of the Alzheimer type. Upon further examination, the authors noted that for both men and women, every two-point increase in the modified Mediterranean diet score meant an 8% lower risk of developing dementia.

    When the researchers differentiated between dementia of the Alzheimer type and dementia of the non-Alzheimer type, they found that the association with a higher modified Mediterranean diet score was stronger between women and non-Alzheimer type dementia and between men and Alzheimer type dementia.

    What’s the Take Home?

    This long-term, large-scale study just adds to the evidence that a Mediterranean-style diet protects the brain from dementia.



    1. Harlan TS. How the Standard American Diet (SAD) affects the brain. Dr. Gourmet. Accessed February 8, 2023.
    2. Harlan TS. 4 ways to protect your brain with diet. Dr. Gourmet. Accessed February 8, 2023.
    3. Andreu-Reinón ME, Chirlaque MD, Gavrila D, et al. Mediterranean diet and risk of dementia and Alzheimer’s disease in the EPIC-Spain dementia cohort study. Nutrients. 2021;13(2):700. doi:10.3390/nu13020700

    Dr. Gourmet is the definitive health and nutrition web resource for both physicians and patients with evidence-based resources including special diets for coumadin users, patients with GERD/acid reflux, celiac disease, type 2 diabetes, low sodium diets (1500 mg/d), and lactose intolerance. 

    Timothy S. Harlan, MD, FACP, CCMS, is a practicing, board-certified Internist. He is currently an Associate Professor of Medicine at George Washington University and Director of the GW Culinary Medicine Program.

    Health meets Food: the Culinary Medicine Curriculum, is an innovative program teaching medical students about diet and lifestyle that bridges the gap between the basic sciences, clinical medicine, the community, and culinary education. Medical students work side-by-side in the kitchen with culinary students to teach each other, and most importantly, teach the community and patients how to return to their kitchens and transform their health. 

    He served as Associate Dean for Clinical Services at Tulane University School of Medicine and is the founder and Senior Advisor of the Goldring Center for Culinary Medicine, the first-of-its-kind teaching kitchen operated by a medical school.

    Dr Harlan attended medical school at Emory University School of Medicine in Atlanta, Georgia, and pursued his residency at Emory University School of Medicine Affiliated Hospitals in Atlanta, GA.