Don’t Rely on Amazon for Legitimate Supplements, Study Finds

Man with supplements and computer

kovaciclea / Getty Images

Key Takeaways

  • A new study found that of a small sample of immune-boosting supplements purchased on Amazon, more than half of the products’ contents were not reflected accurately on the facts label.
  • When you’re choosing supplements, look for those that are third-party tested or have a Good Manufacturing Practices certification. That way, you can know that the supplement you’re buying contains what the supplement facts label claims.
  • Before you start taking any supplement, make sure to talk to your provider about whether it’s safe and whether you truly need the product.

It’s easier than ever to buy supplements online, but you might want to think twice before you do so.

Researchers from the University of Mississippi and the Uniformed Services University tested 30 immune-supporting supplements bought on Amazon and found that only 13 actually contained what was claimed on the product’s label.

How can you tell that you’re truly getting what you paid for if you buy supplements online? Here’s what experts say.

What Are You Really Getting When You Buy Supplements Online?

Supplements can be costly, but many people feel that they’re a worthy investment because they assume the products live up to the claims on the label—for example, helping their body fight off illness with immune-boosting powers.

How trustworthy are those labels, though?

To find out, researchers searched Amazon for the keyword immune in “all departments,” then filtered the results by “featured” to look at which products came up. Then, the researchers chose the first 30 dietary supplement products that were rated with four or more stars.

Researchers purchased one sample of each product and sent it to the University of Mississippi’s National Center for Natural Products Research to be analyzed.

Labels vs. Actual Contents

The first step was to look at what the product labels claimed was in the product—that is, the list of ingredients. Then, the researchers tested the products to find out what was actually in the bottle and compared those results to what the labels said.

After testing 30 supplements, the researchers found that:

  • 17 products had inaccurate labels
  • 13 labels listed ingredients that were not detected in the actual product
  • 9 products had substances in them that were not listed on the labels
  • 15 product labels had “scientific-sounding” claims on them that used terms like “research-based” or “research-supported,” but there was no substantial evidence to back up those claims—including third-party certification

In other words, for consumers who purchased any of those 30 products from Amazon, there was a good chance they were misled.

Are Supplements on Amazon Regulated?

There was no regulation for supplement manufacturers in the United States before 1994. That year, the government created the Dietary Supplement Health and Education Act (DSHEA), which said that the manufacturers and distributors of dietary supplements could not market adulterated products or products that were misbranded.

The act is still in effect today; however, it still does not require supplements to be approved by the government for safety or efficacy. It also does not require the Food and Drug Administration (FDA) to approve the labeling of supplements.

Instead of leaning on a third party to verify what they’ve claimed, the manufacturer is responsible for making sure that their products are safe and lawful, and that any claims they make on the labels are accurate and not misleading to consumers.

Is Anyone Checking Supplements for Safety and Quality?

There are some things that these governing bodies do, though: For example, the FDA may inspect manufacturing facilities for product quality and labeling, track reports of adverse events, and take action to remove any adulterated or misbranded products from the market.

Likewise, the Federal Trade Commission (FTC) can stop deceptive and unfair practices by companies making and selling products, including false or unsubstantiated marketing claims.

However, the accurate labeling of supplements is still ultimately left up to manufacturers.

A Changing World, But No Changing Rules

The rules may have seemed like a good enough way to protect consumers when they were established almost 30 years ago, but times have changed.

In the early 1990s, the internet didn’t play such a big role in our daily lives, let alone as a purchasing platform.

In the decades since, the supplement market has also grown by leaps and bounds—the problem is that the DSHEA has not kept pace.

Is Amazon Doing Anything?

Since December 2020, Amazon has required sellers to provide quality control documentation and the testing results (certificate of analysis) for supplements that are sold on their platform.

However, at this time, it does not appear that Amazon does quality checks on the actual products, which means it’s still possible for supplement labels to be mismatched with the actual contents of a product.

That possibility is evidenced by the recent study, which was done after Amazon’s rules about supplements for sellers had been put in place.

Not Surprising, Still Concerning

“I was not overly surprised by these findings, as the FDA does not test supplements before they are sold to consumers,” Hailey Crean, MS, RD, CDCES, a Boston-based registered dietitian and certified diabetes care and education specialist, told Verywell.

Sarah Anzlovar, MS, RDN, LDN, a registered dietitian and the owner of Sarah Gold Nutrition, told Verywell that “it’s not uncommon for supplements to have additional ingredients not listed on the label, contain more or less of an active ingredient than the label states, or to contain harmful contaminants like heavy metals.”

Anzlovar said that since complying with the safety guidelines is up to the companies, it’s possible that “many false or misleading claims will go undetected for years.”

The recent study was far from the first to show that supplement contents can stray—sometimes a lot—from what their labels state.

A study published in the Journal of Alternative and Complementary Medicine showed that among a sample of 12 supplement formulations being marketed for brain health:

  • 67% (or 8 products) had at least one ingredient listed on the Supplement Facts label that was not detected through analysis
  • Compounds that were not reported on the label were detected in 83% of the supplements (10 products)

The researchers also noted that the “scientific-sounding claims” on the label made were not, in fact, supported by science.

How to Buy Supplements Safely

In a perfect world, every supplement you could buy would contain exactly what is on the label, and any claims made would accurately reflect what the supplement could do for your body.

Since we know that’s not the case, what’s the safest way to buy supplements?

According to Crean, look for certification of third party testing from a trusted source, like USP or NSF, when you’re buying supplements.

ConsumerLab also does significant testing,” Anzlovar said. “Some companies use other third-party testing agencies or have in-house testing that may be just as good [as the bigger ones].”

Verifying that a supplement brand follows Good Manufacturing Practices (GMPs) helps assure that the identity, strength, quality, and purity of the product are accurate. Even though all manufacturers are expected to follow GMP guidelines, being GMP certified means that they have actually followed them.

That said, even products that are GMP certified or are third-party tested are not necessarily safe and effective for you.

Crean said you should always talk to your provider, a dietitian, or a pharmacist to figure out whether you actually need a supplement—and if you do, whether you would be better off getting what you need through your diet.

What This Means for You

If you order supplements on Amazon, you could be getting products that don’t offer what the labels claim. Looking for supplements that are third-party or GMP certified can help you reduce your risk of getting a product that’s not what it claims to be.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Crawford C, Avula B, Lindsey AT, et al. Analysis of select dietary supplement products marketed to support or boost the immune system. JAMA Netw Open. 2022;5(8):e2226040. doi:10.1001/jamanetworkopen.2022.26040

  2. Food and Drug Administration. Dietary supplements.

  3. Federal Trade Commission. Dietary supplements.

  4. Amazon Seller Central. Dietary supplements.

  5. Crawford C, Boyd C, Avula B, Wang YH, Khan IA, Deuster PA. A public health issue: dietary supplements promoted for brain health and cognitive performance. J Altern Complement Med. 2020;26(4):265-272. doi:10.1089/acm.2019.0447