A systematic review and dose response meta analysis of Omega 3 supplementation on cognitive function.
Level 1 - systematic review of randomized trials
Systematic review and dose-response meta-analysis of randomized controlled trials
PubMed 40836005 · doi:10.1038/s41598-025-16129-8
What was done
A systematic review and dose-response random-effects meta-analysis of randomized controlled trials (RCTs) searched across PubMed, Scopus, and ISI Web of Science up to December 2024. The authors evaluated the relationship between omega-3 dosage and adult cognitive outcomes, calculating standardized mean differences (SMDs) and 95% confidence intervals (CIs) per 2,000 mg/day increment. Evidence certainty was assessed using the GRADE approach.
What was found
Based on 58 included RCTs, each 2,000 mg/day increment of omega-3 was associated with significant improvements in: - Attention: SMD 0.98 (95% CI: 0.41, 1.54; GRADE = low) - Perceptual speed: SMD 0.50 (95% CI: 0.05, 0.95; GRADE = moderate) - Language: SMD 0.98 (95% CI: 0.41, 1.54; GRADE = low) - Primary memory: SMD 0.87 (95% CI: 0.17, 1.56; GRADE = moderate) - Visuospatial functions: SMD 0.86 (95% CI: 0.46, 1.27; GRADE = moderate) - Global cognitive abilities: SMD 1.08 (95% CI: 0.73, 1.44; GRADE = low) Non-linear dose-response curves were observed: episodic memory initially decreased and then increased at higher doses (P non-linearity = 0.01, P dose-response = 0.005), whereas global cognitive ability initially increased and then declined at higher doses (P non-linearity = 0.008, P dose-response = 0.002).
Why it matters
This review quantifies domain-specific cognitive responses to omega-3 intake in adults and demonstrates that cognitive benefits do not follow a simple linear pattern, with global cognition tapering at higher doses.
Limits
The total participant count, follow-up durations, specific EPA/DHA ratios, and baseline cognitive status of participants were not reported in the abstract. GRADE certainty ratings were only low to moderate across all evaluated cognitive domains.
Cited by
- supports Omega-3 supplementation reduces inflammation and aids cognitive function.