Omega-3 fatty acids and cardiovascular risk-related metabolic markers in diverse populations: a meta-analysis of randomized trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials.
PubMed 41494879 · doi:10.1016/j.numecd.2025.104488
What was done
A systematic review and meta-analysis searched PubMed, EMBASE, Web of Science, and the Cochrane Library through October 11, 2024. The authors included randomized controlled trials evaluating the effects of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on metabolic and cardiovascular risk markers, including lipid profiles (triacylglycerol [TG], LDL, HDL, total cholesterol [TC]), apolipoproteins, adipokines (adiponectin), HbA1c, C-reactive protein (CRP), and oxidative stress biomarkers across various populations.
What was found
Across 24 studies comprising 2,043 subjects, omega-3 PUFA supplementation showed statistically significant effects: - TG decreased by 16.95 mg/dl (21 trials, n = 1,491; 95% CI: -23.25 to -10.66). - HDL increased by 1.55 mg/dl (22 trials, n = 1,914; 95% CI: 0.69 to 2.42). - Adiponectin increased by 0.96 μg/ml (3 trials, n = 198; 95% CI: 0.03 to 1.80). - HbA1c decreased by 0.17% (3 trials, n = 283; 95% CI: -0.29 to -0.04). - LDL decreased by 10.98 mg/dl in women (4 trials, n = 236; 95% CI: -19.41 to -2.50) and by 13.77 mg/dl in polycystic ovary syndrome (PCOS) (3 trials, n = 180; 95% CI: -22.83 to -4.70). - TC decreased by 15.58 mg/dl in women (4 trials, n = 236; 95% CI: -24.64 to -6.53).
Why it matters
This meta-analysis synthesizes randomized trial evidence indicating that omega-3 supplementation improves key cardiometabolic markers, particularly triglycerides, with potential subgroup-specific lipid improvements in women and individuals with PCOS.
Limits
Several secondary outcomes (adiponectin, HbA1c, and subgroup analyses for LDL and TC) were based on very few trials (3 to 4 studies) with small sample sizes (180 to 283 subjects). The abstract does not report specific omega-3 dosages, formulation ratios (EPA vs. DHA), treatment durations, adverse effects, or numeric results for CRP and oxidative stress biomarkers. Hard clinical cardiovascular outcomes were not evaluated.