Effect of Omega-3, Lutein, Other Nutrient Supplements on Cognitive Function

Study Questions:

Is there an effect of oral supplementation with nutrients on cognitive function?


In a double-masked randomized clinical trial (the Age-Related Eye Disease Study 2 [AREDS2]), retinal specialists enrolled persons with late age-related macular degeneration (AMD) from October 2006 to December 2012. Validated cognitive function tests were administered via telephone by trained personnel at baseline and every 2 years during the 5-year study. Long-chain polyunsaturated fatty acids (LCPUFAs) (1 g) and/or lutein (10 mg)/zeaxanthin (2 mg) versus placebo were tested in a factorial design. All participants were also given varying combinations of vitamins C, E, beta carotene, and zinc.


A total of 89% (3,741/4,203) of AREDS2 participants enrolled in the ancillary cognitive function study, and 93.6% (3,501/3,741) underwent cognitive function testing. Mean (standard deviation) age was 72.7 (7.7) years, and 57.5% were women. There were no statistically significant differences in change of scores based on supplements with LCPUFAs or lutein/zeaxanthin. Analyses were also conducted to assess for potential interactions between LCPUFAs and lutein/zeaxanthin, and none were found to be significant.


Among older persons with AMD, oral supplementation with LCPUFAs or lutein/zeaxanthin had no statistically significant effect on cognitive function.


Worse cognitive function was associated with increasing age, lower education level, male sex, hypertension, and other cardiovascular disease including stroke. During the study, the same risk factors were associated with a greater decline in cognitive function test scores. The study has limited generalizability, considering the cohort was well educated and well nourished.

Clinical Topics: Dyslipidemia, Geriatric Cardiology, Prevention, Lipid Metabolism, Nonstatins, Diet

Keywords: beta Carotene, Cognition, Dietary Supplements, Fatty Acids, Omega-3, Geriatrics, Lutein, Macular Degeneration, Primary Prevention, Retina, Risk Factors, Vitamins, Zinc

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