Some sage consumer advice: be discerning about where you buy supplements.

In a recent study by scientists at Uniformed Services University, researchers analyzed 30 health supplements sold on Amazon. Their goal was to investigate whether the products contained the ingredients listed on their labels and in the stated doses.

Out of the 30 products tested, the researchers found that 17 had inaccurate labels. 

Thirteen claimed to contain molecules that didn’t show up at all. In some products, as many as six listed ingredients were missing, and in one product, only a trace amount of one of the main ingredients was present.

Perhaps more troubling, nine of the supplements contained substances not listed on the label. 

Fifteen used terms such as “research based,” “scientifically proven,” or “backed by science” on their packaging, yet none cited research to support their claims.

Sixteen made claims such as “third party tested,” “lab tested verified,” and “quality guaranteed,” though none had a third-party certification seal. 

Even some of the accurately labeled products were duds: according to the scientists’ scoring system, three of the supplements were considered “no-go” or “risky” based on the quality of the ingredients they contained and the dubious claims printed on the packaging. 

Fortunately, choosing the right supplements is straightforward when you know what to look for. Here are some heuristics to help:

 Only buy supplements from companies that . . .

  • Cite peer-reviewed and relevant research to support their claims (if these aren’t present on Amazon, you should be able to find these studies on the manufacturer’s website)
  • Use reputable labs to test their products and print a third-party certification seal on their labels
  • Are transparent about every dose and ingredient in their products (no “proprietary blends” or “complexes”)
  • Manufacture their products in NSF-certified and FDA-inspected and cGMP-compliant facilities 
  • Have thousands of favorable reviews from verified customers (this may not be the case with smaller, fledgling companies, but it should be with established ones)

And if you want a supplement company that meets all these criteria, try Legion.

All our supplements—from protein powder to pre-workout, and fat burners to fish oil—contain clinically effective doses of scientifically proven ingredients.

They’re also analyzed for purity and potency in a state-of-the-art ISO 17025 accredited lab and backed by tens of thousands of positive reviews from real customers. 

And you feel confused about what supplements you should take to reach your health and fitness goals, take the Legion Supplement Finder Quiz, and in less than a minute, you’ll know exactly what supplements are right for you. Click here to check it out.

Takeaway: Supplement companies regularly lie about the contents of their products. Protect yourself by only buying supplements from reputable companies that support their claims with research, test their products in reputable labs, transparently list all ingredients and doses, manufacture in certified facilities, and have positive customer reviews, such as Legion.

This article is part of our weekly Research Review series, which explores a scientific study on diet, exercise, supplementation, mindset, or lifestyle that will help you gain muscle and strength, lose fat, perform and feel better, live longer, and get and stay healthier. 

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