Peer-reviewed study
Fish oil is not a direct muscle-building replacement
The effects of omega-3 polyunsaturated fatty acids on muscle and whole-body protein synthesis: a systematic review and meta-analysis
Last updated 2026-07-21
Source details
PubMed-linked study details.
- Authors
- Therdyothin et al.
- Journal
- Nutrition Reviews. 2025.
- Identifiers
- PMID 38777807 · DOI 10.1093/nutrit/nuae055
Honest limits
What this study does not prove.
Only eight trials qualified, and the whole-body result came from three comparisons. Fish oil is not established as a muscle builder or a substitute for enough protein and progressive resistance training.
Kris's practical takeaway
Here's what to do with it.
The review found no clear increase in muscle protein synthesis. Three pooled comparisons suggested higher whole-body protein synthesis, but that is not the same as proving muscle gain.
What to remember
Three useful reminders.
Protein and lifting build the foundation
A useful supplement does not have to be a muscle builder
The honest omega-3 result includes what did not improve
Related questions
Questions this research helps answer.
Omega-3 and recovery answer
Does omega-3 help workout recovery?
Omega-3 may modestly improve some soreness and recovery markers, but the studies do not show a guaranteed benefit for every person or workout. Training load, enough food, protein, and sleep remain the foundation; fish oil is only an optional support.
Omega-3 and muscle answer
Does fish oil build muscle?
Fish oil is not a muscle builder by itself. A systematic review found no clear increase in muscle protein synthesis. Three pooled comparisons suggested higher whole-body protein synthesis, but that is not the same as proving muscle gain.
Omega-3 study amounts answer
What omega-3 amount did exercise studies test?
The studies did not test one universal amount. A 2026 recovery meta-analysis reported stronger pooled signals in trials using at least 2 grams per day of combined EPA and DHA for at least six weeks, but that subgroup result is not a personal dosing rule.
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