The connection between brain health and nutrition has been making headlines over the last several years, and this connection is increasingly supported by a growing body of evidence demonstrating a correlation between what you eat and your cognition. A study published in Neurology in 2018 found that a healthy diet increases total brain volume, potentially offsetting age-related shrinkage.1
The study established that people who eat a diet rich in vegetables, fruits, nuts, and fish may have bigger brains.1 Researchers found that after adjusting for age, sex, education, smoking, and physical activity, a higher diet score was linked to larger total brain volume. Those who consumed a better diet had an average of two milliliters more total brain volume than those who did not. To compare, having a brain volume that is 3.6 milliliters smaller is equivalent to one year of aging.1
People with greater brain volume have been shown in other studies to have better cognitive abilities, so initiatives that help improve diet quality may be a good strategy to maintain thinking skills in older adults.
The above quote is from study author Meike W. Vernooij, MD, PhD, of the Erasmus University Medical Center in Rotterdam, the Netherlands, who also said, “More research is needed to confirm these results and to examine the pathways through which diet can affect the brain.”1
In the following video, IFM educator Robert Rountree, MD, talks about the growing concern about brain health and its flipside, cognitive decline, among his patients.
Accumulating evidence suggests that nutrition is important for optimizing cognition and reducing the risk of Alzheimer’s disease (AD), the most common form of dementia and the most clinically significant type of cognitive decline.2 A 2019 review examining the role of nutrition on cognition and AD, with specific emphasis on the Mediterranean diet and its key nutritional components like xanthophyll, carotenoids, and omega-3 fatty acids, found strong evidence that adhering to this dietary pattern can play a positive role in cognitive health among healthy individuals and reduce their risk of developing AD.2 Recent pilot work in which individuals with AD were supplemented with a combination of carotenoids and omega-3 fatty acids yielded positive results in terms of biochemical response and improvements in the ability to perform daily activities.3
In 2018, the first randomized controlled trial of its kind also found that a Mediterranean-like whole-foods diet could slow down age-related cognitive decline, helping to prevent cognitive impairment and dementia.4 Greater adherence to the Mediterranean diet and other emerging healthy diets has been related to decreased risks of several age-related health conditions, including cognitive decline, cognitive impairment, and dementia.4,5,6 Similar results were also observed in the few population-based studies that have used culturally adapted Mediterranean-like dietary patterns such as the MIND diet, the Prudent diet, and the Baltic Sea Diet.4,7 More recently, a longitudinal study of 949 women from the Boston Puerto Rican Health Study cohort suggests that lower baseline plasma pyridoxal-5′-phosphate (PLP, vitamin B-6) is associated with increased odds of two-year cognitive decline, including executive function and memory.8
New research also sheds light on the idea that as you age, who you eat with may be just as important as what you eat. A recent study indicates that a socially integrated lifestyle in the later stages of life support brain health by protecting against cognitive decline and dementia.9 Female respondents with compromised nutritional status eating their meals alone exhibited a greater decrease in SPMSQ scores compared with those who had a normal nutritional status and who were eating their meals with others. The study’s authors suggest that nutritional programs for the elderly should focus on what they eat as well as with whom they eat their meals to prevent social isolation.9
The clinical understanding of how nutrition and other lifestyle factors impact cognition, overall brain health, and brain structure continues to evolve, and some studies have shown that nutrition interventions can prevent or even reverse cognitive decline. Implementing early interventions focused on modifiable risk factors like nutrition for cognitive decline at midlife is a strategy used by many Functional Medicine practitioners, and one that continues to be backed by emerging research.
- Croll PH, Voortman T, Ikram MA, et al. Better diet quality relates to larger brain tissue volumes: the Rotterdam Study. Neurology. 2018;90(24):e2166-e2173. doi:1212/WNL.0000000000005691
- Power R, Prado-Cabrero A, Mulcahy R, Howard A, Nolan JM. The role of nutrition for the aging population: implications for cognition and Alzheimer’s disease. Annu Rev Food Sci Technol. 2019;10:619-639. doi:1146/annurev-food-030216-030125
- Nolan JM, Mulcahy R, Power R, Moran R, Howard AN. Nutritional intervention to prevent Alzheimer’s disease: potential benefits of xanthophyll carotenoids and omega-3 fatty acids combined. J Alzheimers Dis. 2018;64(2):367-378. doi:3233/JAD-180160
- Marseglia A, Xu W, Fratiglioni L, et al. Effect of the NU-AGE diet on cognitive functioning in older adults: a randomized controlled trial. Front Physiol. 2018;9:349. doi:3389/fphys.2018.00349
- Morris MC, Tangney CC, Wang Y, et al. MIND diet slows cognitive decline with aging. Alzheimers Dement. 2015;11(9):1015-1022. doi:1016/j.jalz.2015.04.011
- Pistollato F, Iglesias RC, Ruiz R, et al. Nutritional patterns associated with the maintenance of neurocognitive functions and the risk of dementia and Alzheimer’s disease: a focus on human studies. Pharmacol Res. 2018;131:32-43. doi:1016/j.phrs.2018.03.012
- Chen X, Maguire B, Brodaty H, O’Leary F. Dietary patterns and cognitive health in older adults: a systematic review. J Alzheimers Dis. 2019;67(2):583-619. doi:3233/JAD-180468
- Palacios N, Scott T, Sahasrabudhe N, Gao X, Tucker KL. Lower plasma vitamin B-6 is associated with 2-year cognitive decline in the Boston Puerto Rican Health Study. J Nutr. 2019;149(4):635-641. doi:1093/jn/nxy268
- Li CL, Tung HJ, Yeh MC. Combined effect of eating alone and a poor nutritional status on cognitive decline among older adults in Taiwan. Asia Pac J Clin Nutr. 2018;27(3):686-694. doi:6133/apjcn.092017.05