The Influence of n-3PUFA Supplementation on Muscle Strength, Mass, and Function: A Systematic Review and Meta-Analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized trials assessed with Cochrane RoB2
PubMed 36811583 · doi:10.1016/j.advnut.2022.11.005
What was done
A systematic review and three-level random-effects meta-analysis evaluated the effects of omega-3 polyunsaturated fatty acid (n-3PUFA) supplementation on muscle mass, strength, and function in healthy adults. Four databases (Medline, Embase, Cochrane CENTRAL, and SportDiscus) were searched. Risk of bias was evaluated using the Cochrane RoB2 tool, and evidence certainty was graded via NutriGrade. Subgroup analyses stratified participants by age (<60 vs. ≥60 years), daily dosage (<2 vs. ≥2 g/day), and background exercise (resistance training vs. none/other).
What was found
The meta-analysis included 14 studies comprising 1,443 participants (913 females, 520 males) and 52 outcome measures. Compared to placebo, n-3PUFA supplementation showed no significant effect on muscle mass (SMD = 0.07, 95% CI: -0.02 to 0.17, P = 0.11) or muscle function (SMD = 0.03, 95% CI: -0.09 to 0.15, P = 0.58). Supplementation had a very small but statistically significant positive effect on muscle strength (SMD = 0.12, 95% CI: 0.006 to 0.24, P = 0.04). Subgroup variables (age, dose, resistance training) did not significantly modify these outcomes.
Why it matters
This review clarifies conflicting literature by demonstrating that omega-3 supplementation provides at best a clinically marginal improvement in muscle strength, with no detectable benefit for muscle mass or functional capacity in healthy adults.
Limits
The primary studies exhibited an overall high risk of bias, resulting in a moderate NutriGrade certainty rating. The observed strength benefit was very small and close to the threshold of non-significance (P = 0.04). Findings apply only to healthy populations and cannot be generalized to clinical cohorts experiencing muscle wasting or cachexia.
Cited by
- supports Omega-3 fatty acid supplementation (EPA and DHA) improves overall muscle strength, specifically lower extremity strength.