Mediterranean Diet Improves Cognitive Function in Elderly Subjects

by | Apr 29, 2016 | 2015, Brain Health, Cognitive Health, Mediterranean Diet

Written by Greg Arnold, DC, CSCS. This study shows that a Mediterranean diet with added olive oil and nuts significantly improved brain function in the elderly.

Alzheimer’s disease is the most common type of dementia (2) and the most significant contributor to the $215 billion that dementia costs our healthcare system each year (2). While 5.1 million Americans have Alzheimer’s, another 5.4 million are estimated to have cognitive impairment without dementia (3), totaling more than 10 million Americans with at least some form of cognitive impairment.

There are no effective prescription medications proven to be very helpful to treat Alzheimer’s disease after it’s been diagnosed (4) or to even prevent its progression in patients in the early stages of dementia onset (5). So identifying affordable, effective ways to help prevent dementia or delay its onset is of primary importance.

Now a new study (6) suggests that consuming a Mediterranean Diet, which is plant-based, antioxidant-rich and proven to elicit numerous health benefits (7), may help improve cognitive function in elderly subjects. Previous research has shown that cell damage in the form of oxidative stress plays “a major role” in cognitive decline and neurodegenerative disorders” (8). The new study involved 334 healthy subjects (164 males, 170 females) aged 61 to 72 participating in the PREDIMED study (9). They consumed either:

  • A Mediterranean diet with 1 liter of olive oil supplemented each week (127 subjects)
  • A Mediterranean diet supplemented with 30 grams of mixed nuts per day (15 grams of walnuts, 7.5 grams of hazelnuts, and 7.5 grams of almonds = 112 subjects)
  • A Control diet with instructions on how to consume a low-fat diet (95 subjects).

After an average of 4.1 years of follow-up, those in the Mediterranean Diet plus olive oil saw an 11.4% increase in a measure of total memory called Rey Auditory Verbal Learning Test (39.31 to 43.81) compared to a 10.7% increase in the Mediterranean diet plus nuts group (39.46 to 43.72) and a 5.35% increase in the control group (39.24 to 41.34) (p = 0.49). In another test called the Color Trail Test which measures attention and eye-hand reflexes, the Mediterranean diet plus olive oil group had a 9.3% improvement (62.6 to 56.83) compared to a 4% decrease in the Mediterranean diet plus nuts group (61.15 to 63.63) and a 7.9% decrease in the control group (57 to 61.53) (p = 0.045).

For the researchers, “in an older population, a Mediterranean diet supplemented with olive oil or nuts may counteract age-related cognitive decline” and that “The lack of effective treatments for cognitive decline and dementia points to the need of preventive strategies to delay the onset and/or minimize the effects of these devastating conditions.” The researcher did go on to admit that while “The present results with the Mediterranean diet are encouraging, further investigation is warranted.”

Source:  Valls-Pedret, Cinta, et al. “Mediterranean diet and age-related cognitive decline: a randomized clinical trial.” JAMA internal medicine 175.7 (2015): 1094-1103.

© 2015 American Medical Association. All rights reserved

Posted June 1, 2015.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com.

References:

  1. Ritchie K, Lovestone S. The dementias. Lancet. 2002;360(9347):1759-1766.
  2. “Prevalence of Alzheimer’s Disease” posted on the National Institute of Aging website
  3. Blassman PL. Prevalence of Cognitive Impairment without Dementia in the United States. Ann Intern Med. 2008 March 18; 148(6): 427–434
  4. Iqbal K, Liu F, Gong CX. Alzheimer disease therapeutics: focus on the disease and not just plaques and tangles. Biochem Pharmacol. 2014;88 (4):631-639.
  5. Cooper C, Li R, Lyketsos C, Livingston G. Treatment formild cognitive impairment: systematic review. Br J Psychiatry. 2013;203(3):255-264
  6. Valls-Pedret C. Mediterranean Diet and Age-Related Cognitive Decline: A Randomized Clinical Trial. JAMA Intern Med. 2015 May 11. doi: 10.1001/jamainternmed.2015.1668. [Epub ahead of print]
  7. von Bernhardi R, Eugenin J. Alzheimer’s disease: redox dysregulation as a common denominator for diverse pathogenic mechanisms. Antioxid Redox Signal. 2012;16(9):974-1031
  8. Sofi F, Abbate R, Gensini GF, Casini A. Accruing evidence on benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis. Am J Clin Nutr. 2010;92(5):1189-1196
  9. Estruch R, Ros E, Salas-Salvado J, et al; PREDIMED Study Investigators. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med. 2013;368(14):1279-1290.