Omega-3 fatty acid, carotenoid and vitamin E supplementation improves working memory in older adults: A randomised clinical trial

Power et al., 2022 | Clin Nutr | Rct

Citation

Power Rebecca, Nolan John M, ... Mulcahy Ríona. Omega-3 fatty acid, carotenoid and vitamin E supplementation improves working memory in older adults: A randomised clinical trial. Clin Nutr. 2022-Feb;41(2):405-414. doi:10.1016/j.clnu.2021.12.004

Abstract

BACKGROUND & AIMS: Accumulating evidence suggests that omega-3 fatty acids (ω-3FAs), carotenoids and vitamin E can improve cognitive performance. However, their collective impact on cognition has not yet been investigated in healthy individuals. This study investigated the combined effect of ω-3FA, carotenoid and vitamin E supplementation on the cognitive performance of older adults. METHODS: Cognitively healthy individuals aged ≥65 years consumed daily 1 g fish oil (of which 430 mg docosahexaenoic acid, 90 mg eicosapentaenoic acid), 22 mg carotenoids (10 mg lutein, 10 mg meso-zeaxanthin, 2 mg zeaxanthin) and 15 mg vitamin E or placebo for 24 months in a double-blind, placebo-controlled, randomised clinical trial. RESULTS: Following 24-month supplementation, individuals in the active group (n = 30; aged 69.03 ± 4.41 years; 56.7% female) recorded significantly fewer errors in working memory tasks than individuals receiving placebo (n = 30; aged 69.77 ± 3.74 years; 70% female) (point estimate effect sizes ranged 0.090-0.105). Interestingly, as the cognitive load of the working memory tasks increased, the active group outperformed the placebo group. Statistically significant improvements in tissue carotenoid concentrations, serum xanthophyll carotenoid concentrations and plasma ω-3FA concentrations were also observed in the active group versus placebo (point estimate effect sizes ranged 0.078-0.589). Moreover, the magnitude of change of carotenoid concentrations in tissue, and ω-3FA and carotenoid concentrations in blood were related to the magnitude of change in working memory performance. CONCLUSION: These results support a biologically plausible rationale whereby these nutrients work synergistically, and in a dose-dependent manner, to improve working memory in cognitively healthy older adults. Increasing nutritional intake of carotenoids and ω-3FAs may prove beneficial in reducing cognitive decline and dementia risk in later life. STUDY ID NUMBER: ISRCTN10431469; https://doi.org/10.1186/ISRCTN10431469.

Key Findings

Following 24-month supplementation, individuals in the active group (n = 30; aged 69.03 ± 4.41 years; 56.7% female) recorded significantly fewer errors in working memory tasks than individuals receiving placebo (n = 30; aged 69.77 ± 3.74 years; 70% female) (point estimate effect sizes ranged 0.090-0.105). Interestingly, as the cognitive load of the working memory tasks increased, the active group outperformed the placebo group. Statistically significant improvements in tissue carotenoid concentr

Outcomes Measured

• Requires manual extraction

Population

MeSH Terms

• Aged
• Carotenoids
• Dietary Supplements
• Docosahexaenoic Acids
• Double-Blind Method
• Eicosapentaenoic Acid
• Fatty Acids, Omega-3
• Female
• Fish Oils
• Humans
• Male
• Memory, Short-Term
• Middle Aged
• Neuropsychological Tests
• Vitamin E
• Zeaxanthins

Evidence Classification

• Level: Rct
• Publication Types: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't
• Vertical: omega-3-cognition

Provenance

• PMID: 34999335
• DOI: 10.1016/j.clnu.2021.12.004
• PMCID: Not in PMC
• Verified: 2026-04-09 via PubMed E-utilities API

Source extracted via PubMed E-utilities API on 2026-04-09