Supplement analysis backed by scientific evidence · PT

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Limited evidencePhysical performance

Phosphatidic Acid

A soy-derived lipid that activates mTOR in cell culture. Human trials split cleanly: the positive one used 750 mg/day and came from the ingredient's own research network, while an independent dose-comparison trial found nothing.

What the science says

  • Adds lean mass and strength with resistance training Limited evidence

    At 750 mg/day for 8 weeks in 28 trained subjects, phosphatidic acid produced +2.4 kg lean body mass and +51.9 kg leg press over placebo. An independent 8-week trial in 28 resistance-trained men using 250 or 375 mg/day found significant improvements over time in body mass, lean mass, rectus femoris cross-sectional area and lower-body strength, but no significant group-by-time interactions, meaning the supplement groups did not outperform placebo.

  • Activates mTOR in human muscle Limited evidence

    Phosphatidic acid robustly stimulates mTOR signalling in cultured myoblasts, with soy-derived PA about three times more potent than egg-derived. Whether an oral dose reaches muscle intact is unresolved: a 2017 pharmacokinetic review concluded that ingested PA is largely digested to lysophosphatidic acid and other metabolites, so the human mechanism is inferred rather than demonstrated.

  • Any dose in a blend will work Limited evidence

    Only 750 mg/day has appeared in a positive trial; the doses common in pre-workout blends (200-400 mg) failed to separate from placebo. Many products also stack PA with leucine, HMB and vitamin D3, and the trial of one such combination showed lean mass and strength benefits that cannot be attributed to phosphatidic acid specifically.

Dosage & safety

Studied dose750 mg/day of phosphatidic acid, usually supplied as about 1,500 mg of a 50% soy-lecithin-derived concentrate, taken pre-workout for 8 weeks. Check the label for actual PA content, not concentrate weight. Doses below 750 mg/day have no supporting trial.
SafetyNo serious adverse events in 8-week trials; mild GI upset is the main complaint. Products are soy-derived, which matters for people with soy allergy. No long-term safety data, no data in pregnancy or under 18. Not prohibited in sport. The main practical risk is cost: an effective dose is expensive relative to its uncertain benefit.

Scientific references

Where to buy

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