Nutritional supplements and cognition in healthy aging and mild cognitive impairment patients: a systematic review and network meta-analysis

Liu X

Published in The Journal of Prevention of Alzheimer's Disease

Methodology

Systematic review and network meta-analysis of randomised controlled trials of nutritional supplements reporting cognitive outcomes in healthy ageing or mild cognitive impairment, with SUCRA ranking and GRADE-style certainty assessment.

Key Findings

Network meta-analysis of nutritional supplement trials in healthy older adults and people with mild cognitive impairment found omega-3 fatty acids and B-vitamin combinations ranked highest for global cognition and memory outcomes, while most single-nutrient interventions including vitamin E and standalone vitamin D showed no significant benefit versus placebo; effect sizes were small overall.

Conclusions

DHA alone was found to be beneficial in improving processing speed, whereas vitamin D3 was associated with improvements in visuospatial function.

Limitations

Indirect comparisons across heterogeneous supplements, doses and durations; predominance of short trials with surrogate cognitive endpoints; variable baseline nutritional status; many included trials at moderate risk of bias; ranking probabilities sensitive to sparse networks.