Third-Party Testing: How to Know If Your Supplements Are Safe and Effective

Medically reviewed by Barbie Cervoni MS, RD, CDCES, CDN

Dietary supplements—which are available in pill, liquid, or gummy form—are growing in popularity as countless options pop up in grocery stores and on pharmacy shelves. In fact, many adults and children in the United States take at least one or more supplements. Beyond vitamins and minerals, you also can take herbs, digestive enzymes, adaptogens, amino acids, probiotics, and fish oils in supplement form.

Supplements help you get important nutrients if you don't eat a wide enough variety of nutritious foods or if you have a medical condition that prevents the absorption of specific vitamins and minerals. Additionally, they fill in gaps if there are things you don't like or can't eat due to food allergies. Fish is one of the most prominent sources of omega-3 fatty acids and if you don't like fish or can't hit your nutrient needs through other food sources then you may need to supplement with omega-3 fatty acids.

Related: Verywell Fit's Dietary Supplement Methodology

While most dietary supplements are generally considered safe, they are not without side effects and potential risks. Certain supplements can cause stomach upset, diarrhea, or headaches and others can interact with medications. Because dietary supplements are not regulated by the Food and Drug Administration (FDA), wrong ingredients or too little or too much of the correct ingredients may be added.

However, several independent organizations offer third-party testing to ensure that the product was properly manufactured and that it also is a good quality supplement. Below, we explain what third-party testing is and why it's so important when choosing a dietary supplement.

Related: The 12 Best Supplements, According to a Dietitian

What Is Third-Party Supplement Testing?

Third-party supplement testing occurs when supplements are tested for quality by an organization that was not involved in the production and formulation of the product. Third-party testing programs may help in regulating the purity and safety of supplements since these supplements are exempt from Food and Drug Administration (FDA) approval.

Third-party organizations exist to reduce the number of contaminated products and give consumers a way to verify whether the health claims on the supplement bottle are reliable. Examples of third-party organizations include NSF International, ConsumerLab, and U.S. Pharmacopeia.



How Third-Party Testing Works

When a supplement company chooses to obtain third-party testing and certification, they pay the outside company and provide them with samples of their products to be tested. These organizations then test for ingredient potency and accuracy as well as the presence of heavy metals, bacteria, or mold.

Third-party companies have their own certifications that they put on labels when they test supplements. Getting certified means that the independent organization has reviewed the product and has determined that it complies with the standards for safety, quality, and performance.



While it is not mandatory for supplements to go through this certification process, having a certification is encouraged by the FDA. They also recommend that consumers choose supplements with these third-party certifications.

Related: The 10 Best Vitamin Brands of 2024

Why Is Third-Party Supplement Testing So Important?

The supplement industry is not regulated the same way prescription drugs are and your healthcare provider may not necessarily know how to advise you on supplements and appropriate doses. Ingredients on the supplement label also may not accurately reflect what is inside the supplement or work the way the company claims. The safety and efficacy of supplements are important and that's where third-party testing comes in.

To Validate Ingredients

Unfortunately, it is not uncommon for dietary supplements to be missing key ingredients they claim to contain or be adulterated with unapproved ingredients. From 2007 to 2021, it was found that 1,068 unique products contained unapproved pharmaceutical ingredients. Weight loss and sexual enhancement supplements were most commonly affected. This poses important health risks to consumers.

To Ensure Safety and Purity

Third-party testing also helps ensure the safety and purity of supplements. Dietary supplements may contain mercury, lead, and arsenic. While heavy metals are in the environment and small amounts of exposure are not detrimental, consuming them in large quantities over a long period of time can have many negative consequences.

One analysis showed that 15 protein powder products exceeded the maximum limits of heavy metals proposed by U.S Pharmacopeia standards. Supplements with third-party certifications help ensure the product is free of harmful contaminants.

To Confirm Potency

Choosing supplements that are third-party tested also ensures the potency of the supplement, which refers to the amount or concentration of the key ingredient in order to produce the desired or claimed effect. The FDA has regulations around what can be defined as "high potency" on a supplement label.

This claim can be used to describe individual vitamins or minerals that are present at 100% or more of the Reference Daily Intakes (RDI). Third-party certification can ensure that these claims on the label are actually true.

Related: 5 Potential Benefits (And Some Risks) of Dietary Supplements

Benefits of Choosing Third-Party Tested Supplements

There are many benefits to choosing third-party tested supplements. When you look for third-party certifications, you can have peace of mind knowing that those supplements are safe and effective and that they are not contaminated with unwanted or harmful ingredients and substances.

Additionally, there is an increased likelihood you will achieve your desired results with third-party tested supplements. Certifications provide more assurance that there is an approved amount of the active ingredient in the supplement rather than fillers.



Benefits of Choosing Third-Party Tested Supplements

  • Give peace of mind

  • Validate safety and effectiveness

  • Confirm products are not contaminated

  • Increase efficacy

  • Decrease risk of adverse side effects



Further, third-party tested supplements help decrease the risk of adverse side effects. While all supplements come with their associated risks, third-party tested ones have been vetted for purity of high-quality ingredients that are frequently backed by peer-reviewed scientific studies.

Related: 5 Types of Supplements You Should Always Skip, According to Experts

How to Identify Third-Party Tested Supplements

When buying supplements, look for third-party testing certifications on the product label, or a Certificate of Analysis (COA). Products that have gone through the certification process will have a certification stamp displayed on the label.

These identifiers are proof that the product is safe and contains the ingredients that are claimed to be on the inside. If you don't see any certification stamp or logo on the label, it is likely the product is not certified.

In addition to looking for the certification stamp, do your research to ensure that the third-party testing company is reputable—especially on supplements you will be taking every day. Companies with good reputations and high standards to look for include ConsumerLab, U.S. Pharmacopeia, and NSF International.

Tips for Choosing Safe and Effective Supplements

Supplement shopping can certainly get overwhelming with so many choices on the shelves. Choose supplements from reputable brands that have been third-party tested. Read the product label carefully to ensure that the ingredients reflect what the label is claiming.

If you aren't sure about a certain ingredient, do some research to better understand what is in your supplement, or ask a healthcare professional. Also, before beginning a new supplement, always check with a healthcare provider to make sure it is safe and doesn't interact with any other medications or supplements you are taking.

Related: 6 Things to Look for When Buying Dietary Supplements

Read the original article on Verywell Fitness.