How to tell if your supplement is safe

How to tell if your supplement is safe
March 16, 2023 Marisa Michael

Is your supplement safe? 

A review of supplement data in Nutrients (Martinez-Sans et al., 2017) showed that between 12-58% of supplements sampled and tested were contaminated.

The supplement industry is largely unregulated, leading to false claims on labels. A customer will never know if what is in the bottle is on the label and vice versa.

What contaminants are in supplements?

Contaminants found in supplements (including protein powder and powdered greens) include:

  • Steroids and steroid-like compounds
  • Banned substances
  • Hormones
  • Stimulants such as ephedrine
  • Heavy metals such as mercury and lead

Do supplements have proper dosing?

Supplements often contain an inappropriate dose even if they are not contaminated. Many companies put ingredients in their supplements to make it appear as if they are effective, but it is in too low of a dose to have a useful outcome.

What risks are there to taking supplements?

Depending on the supplement, you could be consuming heavy metals or banned substances, hormones, and steroids that have negative health consequences. Liver failure and even death have been reported in some cases, particularly from Herbalife supplements. 

If the supplement is not clean or safe you are at risk.

How should I decide whether to take a supplement?

There are very few supplements that are safe, effective, and well-researched for sports performance. Keep yourself safe and save some money by asking yourself these questions before purchasing a supplement:

  • Where did I get my information about the supplement? Was it from a reputable, knowledgeable source? Was my source free of conflict-of-interest (hint: your source does not sell the supplement in question)?
  • What do I expect the supplement to do for me? Is there good research to back up the claims?
  • Are there any negative health effects or side effects?
  • Does this supplement interact with any other supplements or medications I am already taking?
  • Do I understand the right dose and timing protocol to make sure I take it correctly?
  • Can the health or performance benefit I are seeking be met another way, such as an adequate diet, better sleep, physical therapy, or medication?
  • Does the supplement fit my budget? Could I spend my money a more effective way, such as buying quality food or implementing an exercise program?

If you want to take a supplement, be sure it is third-party tested. Look for the NSF for Sport or Informed Choice/Informed Sport logos. Even if you’re not an athlete! These third-party testing programs ensure your supplement is free of contamination. Also keep in mind, just because it is safe doesn’t mean you need it or it’s effective. Always¬†check with your healthcare provider before adding or removing supplements from your routine.¬†

To learn more, check out our Ultimate Guide to Useful Sports Supplements on-demand course!


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