If you’ve followed elite running in recent years, you’ve probably seen stories of athletes testing positive for banned substances—only to blame contaminated supplements. Are supplements actually contaminated that frequently? And if professionals are struggling to ensure their supplements are safe, what does that mean for the rest of us?
Risk of contaminated supplements
There is a growing body of evidence that should make all of us, professional runners or otherwise, pause before popping that supposedly healthy pill. Studies looking at dietary supplements across the world have revealed contamination rates from 12 to 58 per cent, either due to accidental contamination or intentional or neglectful mislabelling. Some contain undeclared stimulants, steroids or diuretics—ingredients that could not only trigger a positive drug test but also pose serious health risks.
Unlike prescription drugs, dietary supplements are not strictly regulated. The U.S. Food and Drug Administration (FDA) does not test supplements before they hit the market. Similarly, while the Canadian dietary supplement sector has developed several regulatory standards to ensure safety, they admit these requirements aren’t always correctly implemented. Instead, governing bodies often step in only after problems arise, such as reported adverse effects or failed drug tests. This means the responsibility falls on the consumer to choose products carefully.
Should recreational runners be concerned?
While most runners aren’t subject to anti-doping rules, supplement safety still matters. Contaminants like amphetamines, steroids or stimulants can have harmful long-term effects, even for those not competing professionally. Additionally, misleading labels can mean you’re not getting what you paid for—some supplements have been found to contain far less (or far more) of an ingredient than advertised.
How to protect yourself
To minimize your risk, follow these guidelines:
Look for third-party certification: Organizations like NSF Certified for Sport, Informed Sport and USP test supplements for banned substances and label accuracy. Choosing certified products reduces your risk significantly.
Be skeptical of bold claims: If a supplement promises rapid muscle growth, extreme fat loss or “natural performance enhancement,” it’s a red flag. Many of these products are the ones most often found to contain hidden stimulants or steroids.
Read the label carefully: Ingredients can be listed under unfamiliar names. If you’re unsure about an ingredient, check WADA’s (World Anti-Doping Agency) Prohibited List or consult a sports nutrition expert.
Stick to trusted brands: Established companies with strong reputations for quality control are a safer bet than newer or less regulated brands.
Be cautious with online marketplaces: Some online sellers offer supplements from third-party distributors, which increases the risk of tampered or counterfeit products.
The takeaway
Runners put in a lot of hard work, and the last thing you need is a supplement that sabotages your efforts. While some supplements can support training and recovery, they also come with risks. The best way to stay safe is to prioritize whole foods for nutrition and, if you decide to take supplements, ensure they’re third-party tested and from a trusted source.
