How much omega-3 for muscle growth?

The four-gram trial dissected, what it gave, what it measured, and what it did not

How much omega-3 for muscle growth is a question that comes from one trial, and dissecting it answers every variant, because the number people quote is the trial's dose and the thing people expect is something the trial did not measure. The dose: four grams of EPA and DHA a day, roughly 1.9 grams of EPA and 1.5 grams of DHA from a concentrate, for eight weeks, in a small group of healthy adults, first older and then, in a companion study, younger. What it measured: the rate of muscle protein synthesis, the building of new muscle protein, in response to an infusion of amino acids and insulin that mimics a protein meal, before and after the eight weeks, and it found the rate raised after omega-3, the signalling through the pathway that drives synthesis more responsive, a real and interesting finding about a mechanism, the muscle protein synthesis and omega-3 review's central citation. What it did not measure: muscle size, strength, body composition or anything a lifter can see, over any period, so the trial shows that a large dose of omega-3 for two months made muscle more responsive to a simulated meal in a laboratory and does not show that anyone grew, the difference between a mechanism and an outcome that the growth story skips. Four grams in softgels is the second thing the story skips: thirteen standard 300mg softgels a day, or four concentrate softgels at a gram each, every day for eight weeks, the four-softgel concentrate version being what the trial's subjects effectively took and being, at 60 to 90p a day, the price of the mechanism.

The review that finds no hypertrophy in the trained, the missing claim, the lifter's honest dose, and the question filed

The review that pulls the muscle trials together finds what the single trial could not: across studies of omega-3 supplementation and muscle in trained young adults, there is no consistent gain in muscle size or strength, the raised synthesis in the laboratory not translating into visible growth in people who train, with the clearer signals being in older adults losing muscle and in people immobilised or ill, populations in which an anti-catabolic effect has more to work against, so a young lifter taking four grams a day for growth is taking a dose whose mechanism is real and whose outcome, in their population, the review does not find. The register is consistent with the review: omega-3 holds no growth, muscle, strength or recovery claim, its sentences being heart, brain, vision, triglycerides and blood pressure, and protein holds the register's only growth claim, a contribution to a growth in muscle mass, at the intakes the protein pages set out, so a label may not print omega-3 for muscle and a lifter should not buy it for that. The lifter's honest dose, then, is the oily-fish audit's: 250mg of EPA and DHA a day for the heart claim if oily fish is not eaten twice a week, one standard softgel, or around a gram for the omega-3 index research target, three standard or one concentrate, taken for those reasons at a fatty meal, with the DOMS review's modest soreness finding at gram-and-above doses over weeks a small bonus rather than a reason, and muscle growth left to the four things that build it, a progressive stimulus, protein at around 1.6 grams per kilogram, sufficient energy and sleep. The question filed: no dose of omega-3 grows muscle, the four-gram trial having measured synthesis and not size, the review finding no hypertrophy in the trained, and the register holding no growth claim, with the worked example being omega-3 by the oily-fish audit, one softgel at 17p, £14.99 for 90.

The verdict, a mechanism at four grams and no muscle at any dose

How much omega-3 for muscle growth: no dose, the four-gram trial that the question comes from having given four grams of EPA and DHA a day for eight weeks and measured raised muscle protein synthesis in response to a simulated meal without measuring muscle size, four grams being thirteen standard softgels or four concentrate softgels a day, the review of omega-3 and muscle finding no consistent hypertrophy or strength gain in trained young adults, and the register holding no growth claim for omega-3 while protein holds the only one, so a lifter takes omega-3 by the oily-fish audit, 250mg for the heart claim or a gram for the index, and builds muscle with the stimulus, protein, energy and sleep. Omega-3 by the audit: Futuro Labs Omega 3 Fish Oil, one softgel, 180mg EPA and 120mg DHA, 90 for £14.99 at 17p a day.

What to check on the label

Questions people also ask

How much fish oil should I take to build muscle?

No amount builds muscle: the four-gram-a-day trial found raised muscle protein synthesis in a laboratory without measuring size, the review of omega-3 and muscle finds no consistent hypertrophy in trained young adults, and omega-3 holds no growth claim, so fish oil is dosed by the oily-fish audit and muscle is built by training, protein, energy and sleep.

What did the four-gram omega-3 muscle study actually show?

That eight weeks of four grams of EPA and DHA a day, about 1.9 grams of EPA and 1.5 of DHA, raised the rate of muscle protein synthesis in response to an amino acid and insulin infusion that mimics a meal, a mechanism, in a small group of adults, without measuring muscle size, strength or composition.

How many fish oil capsules is four grams of omega-3?

Thirteen standard 300mg softgels a day, or four concentrate softgels at a gram of EPA and DHA each, every day for eight weeks, the concentrate version costing 60 to 90p a day and being what the trial's subjects effectively took.

Does omega-3 help muscle growth in people who train?

Not consistently: the review finds no reliable gain in muscle size or strength from omega-3 in trained young adults, the clearer signals being in older adults losing muscle and in people immobilised or ill, where an anti-catabolic effect has more to work against.

What omega-3 dose should a lifter actually take?

The oily-fish audit's: 250mg of EPA and DHA a day for the heart claim if oily fish is not eaten twice a week, one standard softgel, or around a gram for the omega-3 index research target, three standard or one concentrate, at a fatty meal and for those reasons.

Sources

1. Smith GI, Atherton P, Reeds DN, et al. Dietary omega-3 fatty acid supplementation increases the rate of muscle protein synthesis in older adults: a randomized controlled trial. American Journal of Clinical Nutrition 2011;93(2):402-412. PubMed record
2. McGlory C, Calder PC, Nunes EA. The influence of omega-3 fatty acids on skeletal muscle protein turnover in health, disuse, and disease. Frontiers in Nutrition 2019;6:144. PubMed record
3. The GB claims register, protein entries: protein contributes to a growth in muscle mass and to the maintenance of muscle mass and of normal bones, authorised for foods that are at least a source of protein. https://www.gov.uk/government/publications/great-britain-nutrition-and-health-claims-nhc-register
4. The muscle protein synthesis literature: resistance exercise and a leucine-rich protein dose of around 20 to 40 grams stimulate muscle protein synthesis for hours, with total daily protein, energy availability and the training stimulus determining net gain, and no trial of magnesium supplementation on muscle protein synthesis in trained adults. PubMed record

Related answers

• Which omega-3 is best for muscle growth?
• How much omega-3 for athletes?
• How much omega-3 daily intake limit should you take?
• How much omega-3 dosage by age should you take?
• How much omega-3 per day for a woman?
• How much omega-3 should a gym goer take daily?