6 Red Flags to Watch for When Buying Supplements Online

6 Red Flags to Watch for When Buying Supplements Online

The fact that many dietary supplements are “natural” does not mean they are safe, and purchasing supplements online is particularly risky because they are often contaminated with other substances. Here are some traps to avoid.

1. Unrealistic Claims

  • As a general rule, avoid any online supplements that promise miracle cures or quick remedies. These claims are misleading at best and may be dangerous.
  • In the U.S., prescription and over-the-counter (OTC) medications may be advertised for the diagnosis, cure, treatment, or prevention of disease. These medicines are rigorously tested by the Food and Drug Administration (FDA) and must demonstrate safety and effectiveness before they can be sold or dispensed.
  • Dietary supplements do not undergo the same testing and approval process as prescription medications do.
  • It’s actually illegal for supplements to be marketed for treating specific diseases or health conditions, so avoid products that boast these claims.
  • Similarly, supplements marketed as alternatives to prescription medicines or steroids should raise a red flag; steer clear of this false advertising.

2. Marketing for Performance Enhancement

  • Be wary of supplements advertised online or promoted on social media for weight loss, athletic performance, or sexual enhancement.
  • The FDA has found that these products are more likely than other supplements to contain banned drugs, controlled substances, and other prescription medications that are associated with serious risks, especially for people with health conditions.
  • Dietary supplements marketed for weight loss and performance enhancement have caused strokes, liver and kidney damage, breathing problems, and even death.

3. Lack of Third-Party Certification

  • Avoid supplements that are not certified by a reputable independent organization, such as ConsumerLab.com, NSF International, or the U.S. Pharmacopeia.
  • Third-party certification means that a supplement has been manufactured safely, contains the ingredients stated on the label, and is free of contaminants.
  • Keep in mind, though, that certification does not guarantee that the supplement is safe or effective.
  • An extra note of caution: Amazon is by far the biggest online marketplace for supplements, responsible for almost 80% of supplement sales. Even though Amazon requires manufacturers to submit quality assurance certificates to sell supplements on the site, a recent study found that 17 of the top 30 immune system supplements were mislabelled (misbranded). Some products contained ingredients not listed on the label, while others did not contain the advertised ingredients.

4. Labels in a Foreign Language

  • The FDA recommends avoiding supplements with labels or packaging predominantly written in a foreign language.
  • This is because regulations and standards for dietary supplements vary worldwide, and the directions may also be unclear. Your best bet for a legal product in the U.S. is to buy one made in the country.

5. Specific FDA Warnings

  • Although the FDA does not test supplements before they reach the market, it can remove them from the market if they are found to be dangerous or fraudulent.
  • Be sure the supplement you are considering does not contain ingredients the FDA has found to be counterfeit.
  • You can find the latest guidance from the FDA on the Health Fraud Product Database or Dietary Supplement Ingredient Directory.

6. Higher Than Recommended Dosage

  • Whether you buy supplements online or at a brick-and-mortar store, keep an eye on how much of your Daily Value (DV) of vitamins and minerals a supplement contains.
  • Supplements that contain more than 100% of the recommended daily intake are more likely to cause side effects. This is especially true for fat-soluble vitamins, which accumulate in the body if you consume too much.

A Note on Dietary Supplements

  • All supplements may cause side effects and interact with medications.
  • For optimal health and safety, discuss the use of any dietary supplement with your healthcare provider before self-treating.
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.
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Megan Nunn headshot

By Megan Nunn, PharmD

Nunn is a community pharmacist in Tennessee with 12 years of experience in medication counseling and immunization.