The Association Between Egg Consumption and Cognitive Function in Older Adults

by | Jan 18, 2024 | 2023, Aging, Brain Health, Cognitive Health, Proteins

Written by Harold Oster, MD. Results suggest that greater egg consumption in older adults is not associated with cognitive impairment.

Protein - eggsDementia is the acquired loss of cognitive function across several domains. The prevalence of dementia has increased and currently affects over 15% of people older than 68 years1. Eggs have high levels of choline2 and the carotenoids, lutein and zeaxanthin3, all of which may have a beneficial effect on cognitive function. While the cholesterol in eggs has been implicated in neurodegenerative disease, consumption of eggs has been shown to benefit cognition in some studies4.

Donna Kritz-Silverstein and Ricki Bettencourt studied the prospective association between egg consumption and cognitive function in older adults. From 1972 to 1974, over six thousand adults in Rancho Bernardo, California were enrolled in a prospective study of heart disease risk factors. At enrollment, information was obtained by questionnaire on weekly consumption of eggs, demographics, medical history, smoking, and alcohol use. Blood pressure, weight, and height were measured, and blood was tested for glucose, cholesterol, and triglycerides. Participants were administered the following cognitive tests at a research center between 1988 and 1991: the Buschke-Fuld Test to evaluate short and long-term memory5, the Heaton Test to assess visual memory6, The Mini-Mental State Examination (MMSE) for global function7, the Blessed Information-Memory-Concentration Test for executive function and concentration8, the Trail-making test to evaluate cognitive flexibility9, and the Category Fluency test to assess semantic memory10.

The authors noted the following:

  • Based on inclusion criteria, the data from 1515 participants was analyzed.
  • Men consumed more eggs than women (4.2 vs. 3.5 per week).
  • After adjustment for covariables, men who consumed more eggs performed better on the Buschke-Fuld Test for both long and short-term memory.
  • Among women, no significant associations were observed between egg intake and cognitive function tests.
  • In the subgroup of men younger than sixty years at enrollment, greater egg consumption was associated with improved performance on the MMSE and the Heaton test of visual memory but worse performance on the Trail-making test of cognitive flexibility.
  • In the subgroup of women younger than sixty years at enrollment, greater egg consumption was associated with higher scores on the Category Fluency test.
  • After adjustment for covariables, egg consumption was not associated with cognitive impairment on any tests.

The authors conclude that increased egg consumption is not associated with cognitive impairment in older adults. In the subgroup of women under sixty years old at enrollment, greater egg consumption was associated with improved category fluency later in life. In contrast, men under sixty at enrollment showed mixed results on later testing. Limitations include using a single questionnaire at enrollment to assess egg intake and the possibility of residual confounding.

Source: Kritz-Silverstein, Donna, and Ricki Bettencourt. “The Longitudinal Association of Egg Consumption with Cognitive Function in Older Men and Women: The Rancho Bernardo Study.” Nutrients 16, no. 1 (2023): 53.

© 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

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Posted January 18, 2024.

Harold Oster, MD graduated from medical school in Miami, Florida in 1992 and moved to Minnesota in 2004. After more than 25 years of practicing Internal Medicine, he recently retired. Dr. Oster is especially interested in nutrition, weight management, and disease prevention.

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