Supplements

Topics

• Creatine

  Creatine is a compound found mainly in meat and fish that helps recycle cellular energy in muscle and brain. Meta-analyses of randomised trials found that creatine taken alongside resistance training increased strength in adults and increased lean tissue mass and strength in older adults. Trials suggest a small benefit for memory, most clearly in older adults, but results are inconsistent. People following vegetarian diets start with lower muscle creatine and may respond more in muscle. Trials of up to about a year found a rise in serum creatinine without changes in kidney filtration in healthy people.

  • Mind
  • Strength
  • Vegan

  5 claims

• Magnesium (sleep)

  Magnesium supplements are widely used to support sleep, but randomised trials in adults give inconsistent results: small trials in older adults found people fell asleep somewhat sooner, while a 2026 systematic review of 12 trials rated the evidence low to very low certainty. Observational studies link better magnesium status with better sleep quality, which does not show cause and effect. The only claim graded moderate concerns safety: high supplemental doses commonly cause loose stools, and authorities set an adult upper level for magnesium from supplements; none of the sleep-benefit claims reach moderate because the trials are few, small, heterogeneous and at risk of bias.

  • Sleep

  5 claims

• Melatonin (sleep)

  Melatonin is a hormone that helps time the body clock, and melatonin supplements are most often made synthetically. Randomised trials show the clearest benefit for jet lag in air travellers crossing five or more time zones. For adults with long-standing sleep difficulties the effects are small and inconsistent: an older meta-analysis found sleep onset about 7 minutes faster, a 2022 meta-analysis found no significant effect in adults, and a 2017 sleep-medicine guideline suggests against it for chronic insomnia. Short-term use appears to be well tolerated in trials, long-term safety data are lacking, and the dose in over-the-counter products often differs from the label.

  • Sleep
  • Vegan

  5 claims