A career-level risk
For athletes subject to drug testing, supplements carry a risk most people never think about: contamination with banned substances. Studies and anti-doping agencies have repeatedly found supplements containing undeclared prohibited compounds (stimulants, steroids, SARMs) — sometimes from cross-contamination in manufacturing, sometimes from deliberate adulteration.
Why 'I didn't know' isn't a defense
Most anti-doping systems operate on strict liability: the athlete is responsible for whatever is in their body, regardless of whether a banned substance was disclosed on a supplement label. So a contaminated product the athlete took in good faith can still cause a failed test and sanctions.
How sport-certification reduces the risk
Specialized programs test supplements specifically for banned substances [1]:
- NSF Certified for Sport — screens products for substances banned in sport, in addition to verifying contents and contaminant limits.
- Informed Sport / Informed Choice — batch-level testing for banned substances (Informed Sport tests every batch) [2].
These go beyond general quality seals (see certification seals compared) by targeting the banned-substance question specifically. They reduce — but can't absolutely guarantee zero — risk.
High-risk categories
The greatest contamination risk is in pre-workouts, 'fat burners,' muscle-building, and 'testosterone booster' products — the same categories most associated with hidden stimulants and adulteration. Simpler, single-ingredient products from reputable brands carry less risk.
Practical guidance
- Use only sport-certified products if you're drug-tested (NSF Certified for Sport, Informed Sport).
- Avoid high-risk categories (pre-workouts, fat burners, 'test boosters').
- Check with your team's anti-doping resources and keep records of what you take.
- Remember strict liability: the responsibility is yours, so verification matters.