Objective: Loneliness enhances risk for episodic memory declines over time. Omega-3 supplementation can improve cognitive function for people experiencing mild cognitive difficulties. Accordingly, we explored whether omega-3 supplementation would attenuate loneliness-related episodic memory problems.
Methods: Participants (n = 138) from a parent randomized controlled trial were randomized to the placebo, 1.25 grams/d of omega-3, or 2.50 grams/d of omega-3 conditions for a 4-month period. They completed a baseline loneliness questionnaire and a battery of cognitive tests both at baseline and at the end of the randomized controlled trial.
Results: After adjustment for baseline verbal episodic memory scores, lonelier people within the placebo condition had poorer verbal episodic memory postsupplementation, as measured by immediate (b = -0.28, t (117) = -2.62, p = .010) and long-delay (b = -0.06, t (116) = -2.07, p = .040) free recall, than their less lonely counterparts. This effect was not observed in the 1.25- and 2.50-grams/d supplementation groups (all p values > .10). The plasma omega-6:omega-3 ratio data mirrored these results. There were no loneliness-related effects of omega-3 supplementation on short-delay recall or the other cognitive tests (all p values > .32).
Conclusion: These results suggest that omega-3 supplementation attenuates loneliness-related verbal episodic memory declines over time and support the use of exploring novel interventions for treating episodic memory problems among lonely people.
Trial registration: clinicaltrials.gov Identifier: NCT00385723.