Supplement analysis backed by scientific evidence · PT

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Limited evidenceLongevity & antioxidants

PQQ

Pyrroloquinoline quinone is marketed on impressive mitochondrial biology that has not translated into convincing human outcomes. The handful of small, mostly manufacturer-funded cognitive trials are suggestive at best, and the exercise trial was negative.

What the science says

  • Cognitive function Limited evidence

    A randomized trial of PQQ disodium salt (roughly 20 mg/day for 12 weeks) reported improvements in selected composite scores of brain function in younger and older adults, and a separate placebo-controlled trial in healthy volunteers found gains limited to a few subtests. Sample sizes are small, outcomes are numerous relative to participants, and the trials are funded by the ingredient manufacturer.

  • Mitochondrial biogenesis and exercise performance Limited evidence

    Three weeks of 20 mg/day PQQ in untrained men produced no improvement in VO2 max or aerobic exercise performance and no meaningful change in circulating indices of mitochondrial biogenesis versus placebo. The mitochondrial story rests on cell and rodent data, not human function.

  • Sleep and fatigue Limited evidence

    Small uncontrolled or single-arm Japanese studies report better sleep-quality and fatigue questionnaire scores after 20 mg/day for 8 weeks. Without adequate blinding and control these are hypothesis-generating only.

Dosage & safety

Studied doseHuman trials almost all use 10-20 mg/day of PQQ disodium salt taken with food, for 8-12 weeks. There is no evidence that higher doses do more, and mitochondrial trials showing nothing used the same 20 mg.
SafetyNo serious adverse events have been reported at 20 mg/day over 12 weeks, with occasional headache, GI upset and sleep changes (both drowsiness and difficulty sleeping) at similar rates to placebo. Long-term human safety data beyond a few months do not exist, and the highest doses tested in humans remain modest. Rodent work at very high doses has shown kidney effects, so do not megadose. Not studied in pregnancy, breastfeeding or children.

Scientific references

Where to buy

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