Effect of 2-y n-3 long-chain polyunsaturated fatty acid supplementation on cognitive function in older people: a randomized, double-blind, controlled trial.
ABSTRACT Increased consumption of n-3 (omega-3) long-chain polyunsaturated fatty acids (LC PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may maintain cognitive function in later life.
We tested the hypothesis that n-3 LC PUFA supplementation would benefit cognitive function in cognitively healthy older people.
At total of 867 cognitively healthy adults, aged 70-79 y, from 20 general practices in England and Wales were randomly assigned into a double-blind controlled trial of daily capsules providing 200 mg EPA plus 500 mg DHA or olive oil for 24 mo. Treatment-allocation codes were obtained from a central computerized randomization service. Trained research nurses administered a battery of cognitive tests, including the primary outcome, the California Verbal Learning Test (CVLT), at baseline and 24 mo. Intention-to-treat analysis of covariance, with adjustment for baseline cognitive scores, age, sex, and age at leaving full-time education, included 748 (86%) individuals who completed the study.
The mean age of participants was 75 y; 55% of the participants were men. Withdrawals and deaths were similar in active (n = 49 and n = 9, respectively) and placebo (n = 53 and n = 8, respectively) arms. Mean (+/-SD) serum EPA and DHA concentrations were significantly higher in the active arm than in the placebo arm at 24 mo (49.9 +/- 2.7 mg EPA/L in the active arm compared with 39.1 +/- 3.1 mg EPA/L in the placebo arm; 95.6 +/- 3.1 mg DHA/L in the active arm compared with 70.7 +/- 2.9 mg DHA/L in the placebo arm). There was no change in cognitive function scores over 24 mo, and intention-to-treat analysis showed no significant differences between trial arms at 24 mo in the CVLT or any secondary cognitive outcome.
Cognitive function did not decline in either study arm over 24 mo. The lack of decline in the control arm and the relatively short intervention period may have limited our ability to detect any potential beneficial effect of fish oil on cognitive function in this study. The Older People And n-3 Long-chain polyunsaturated fatty acids (OPAL) Study was registered at www.controlled-trials.com as ISRCTN 72331636.
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ABSTRACT: As longevity increases, so does the global prevalence of cognitive dysfunction. Numerous lifestyle and/or dietary interventions such as omega-3 fatty acids have been suggested to improve memory. Therefore, this study examined the consistency and strength of the impact of supplementation of omega-3 fatty acids on overall cognitive function using systematic reviews and meta-analytic methods. Of 905 studies retrieved from all searches, 12 randomized controlled trials were included in the meta-analysis. There were differences between studies reporting outcomes for single memory function parameters. Subgroup analysis of doses used (low versus high) indicated that subjects receiving low (<1.73 g/day) doses of omega-3 fatty acids had a significant reduction in cognitive decline rate (-0.07, 95% confidence interval -0.01, -0.02) but there was no evidence for beneficial effects at higher doses (+0.04, 95% confidence interval -0.06, +0.14) compared with the placebo group. This study suggests that omega-3 fatty acids may be beneficial in preventing memory decline at lower doses.International Journal of General Medicine 01/2014; 7:463-73.
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ABSTRACT: 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 (RCT) were randomized to the placebo, 1.25 grams/day of omega-3, or 2.50 grams/day 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 RCT. Results: Controlling for baseline verbal episodic memory scores, lonelier people within the placebo condition had poorer verbal episodic memory post-supplementation, as measured by immediate (b = -0.28, t(117) = -2.62, p = .010) and long-delay (b = -.06, t(116) = -2.07, p = .040) free recall, than their less lonely counterparts. This effect was not observed in the 1.25 grams/day and 2.50 grams/day 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 utility of exploring novel interventions for treating episodic memory problems among lonely people. ClinicalTrials.gov identifier: NCT00385723Psychosomatic Medicine 01/2014; 76:650-658. · 4.09 Impact Factor
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ABSTRACT: Optimal nutrition is one of the most important determinants of healthier ageing, reducing the risk of disability, maintaining mental and physical functions, and thus preserving and ensuring a better quality of life. Dietary intake and nutrient absorption decline with age, thus increasing the risk of malnutrition, morbidity and mortality. Specific nutrients, particularly long-chain omega-3 polyunsaturated fatty acids (PUFAs), might have the potential of preventing and reducing co-morbidities in older adults. Omega-3 PUFAs are able to modulate inflammation, hyperlipidemia, platelet aggregation, and hypertension. Different mechanisms contribute to these effects, including conditioning cell membrane function and composition, eicosanoid production, and gene expression. The present review analyzes the influence of omega-3 PUFAs status and intake on brain function, cardiovascular system, immune function, muscle performance and bone health in older adults. Omega-3 FAs may have substantial benefits in reducing the risk of cognitive decline in older people. The available data encourage higher intakes of omega-3 PUFAs in the diet or via specific supplements. More studies are needed to confirm the role of omega-3 FAs in maintaining bone health and preventing the loss of muscle mass and function associated with ageing. In summary, omega-3 PUFAs are now identified as potential key nutrients, safe and effective in the treatment and prevention of several negative consequences of ageing.Nutrients 10/2014; 6(10):4058-4072. · 3.15 Impact Factor