Strength Review

Up to half of tested supplements contained banned substances

Lab analyses found anabolic agents or other prohibited substances in 14–50% of sampled sports supplement products.

Prevalence of adulteration in dietary supplements and recommendations for safe supplement practices in sport

Jagim AR, Harty PS, Erickson JL, et al. · Front Sports Act Living · 2023

What they studied

Design
Narrative review
Scope
Analytical studies that tested supplement products
Context
60–80% of athletes report using supplements
Focus
Contamination, inadvertent doping and safe-use practices

What they found

  • Between 14% and 50% of analysed supplement samples tested positive for anabolic agents or other prohibited substances.
  • Risks include inadvertent doping, mislabelling, ingredients banned by sport bodies and health risks for some groups.
  • The authors list four safe practices: follow the serving size, check ingredients against the prohibited list, choose third-party certified products and avoid stacking products with overlapping ingredients.

How strong is the evidence

Review

What this design cannot tell us:

  • A narrative review, not a systematic one.
  • Contamination rates vary widely depending on which products and markets were tested.

What it means for your training

  • Buy third-party certified products, stick to the label dose and watch for overlapping ingredients.
  • If you are tested in sport, check every product against the prohibited list before use.

Our summary of the published abstract. Read the original paper for full details.

More on strength

← All studies in the digest