Third-Party Testing for Supplements: Everything You Need to Know

third-party testing

Have you ever heard of third-party testing for supplements?  Many supplement companies are very vague about whether they third-party test and, if they do, what all that entails.  This blog aims to clear up the confusion and misconceptions about third-party testing for supplements.  Additionally, you will learn about why third-party testing is so important in the supplement industry.

What does third-party testing mean?

You might see that a supplement company posted that their products are third-party tested and wonder what that means.  Well, unfortunately, not all third-party testing is the same.  Generally, what third-party testing means is that an organization that is not the supplement company itself evaluates a dietary supplement and vouches for its quality.  The supplement company has to pay the third party and provide them with samples or entire bottles of their product to be tested.

What do they test for?

When a company has their product third-party tested, they could test for various things, including ingredient potency and accuracy (ingredient claims on the label=what is in the finished product), heavy metals, mold, and bacteria.

What a supplement company does or does not test for is exclusively up to that company.  This means that they can pick and choose what they test for. Let’s get into a little more detail about the different types of third-party testing.

Ingredient Potency & Accuracy

When third-party testing for supplements is done to check for ingredient potency and accuracy, the companies are making sure that what the supplement company claims as ingredients on their label aligns with what is actually in the product and the claimed amounts.  For example, if a company claims that they have 15g of protein in their recovery formula, but the third-party testing results only show 12 grams, that supplement company is falsely labeling their product.

As you can tell, this type of third-party testing for supplements can be a considerable risk for a supplement company.  The FDA monitors the nutrition and supplement labeling, and supplement companies can run into problems if they find out that they are overclaiming or underclaiming the ingredients in your product.

The supplement industry is full of supplements with inaccurate labels.  An article by Harvard Health discussed a study that showed that over 20% of the 776 dietary supplements tested contained multiple unapproved ingredients.  Surprisingly, the FDA only announced voluntary recalls for about half of these supplements.

Unfortunately for consumers, the supplement industry is not nearly as rigorously regulated like the prescription industry.  Supplements with inaccurate labels will likely slip through and go unnoticed.  This is why you must ensure that the supplement you are taking is third-party tested for potency and accuracy.

Heavy Metals

This is a test that is strongly encouraged for the safety of customers.  Heavy metals like lead, mercury, cadmium, chromium, and arsenic intoxication have been associated with the use of health and dietary supplements (Abdullah et al., 2019).  These metals are common in the environment and our diets.  In small amounts, these metals can support health.  However, when ingested in large quantities or at elevated doses over time, they can wreak havoc and lead to heavy metal toxicity.

There are several possible side effects of heavy metal toxicity:

  • lowered energy levels
  • brain damage
  • lung damage
  • kidney damage
  • liver damage

Long-term exposure can also lead to progressive physical, muscular, and neurological degeneration that imitates diseases like multiple sclerosis, Parkinson’s, Alzheimer’s, and muscular dystrophy (Jaishankar et al., 2014).  Repeated long-term exposure to some heavy metals may even cause cancer.    Some heavy metals are so toxic that if you ingest even the slightest bit over the amount found naturally in your body from the environment, you will get sick.

The Clean Label Project is a national nonprofit that focuses on health and transparency in labeling.  A study performed by the Clean Label Project found elevated levels of heavy metals in 53 leading protein supplement brands.  Approximately 75% contained measurable lead levels, with plant-based protein powders containing twice as much on average as non-plant-based powders.  Ten percent of whey-based powders tested had lead levels above health guidelines.

As you can see, ensuring a supplement you are taking is third-party tested for heavy metals is extremely important!  Evidence has shown that an alarmingly high rate of supplements contain more than the recommended/allowable levels of heavy metals in their products.

Purity (Mold, Yeast, and Bacteria)


Mold fungi are naturally widespread in the environment and are often present in plant-originated raw materials.  Mold creates spores that are easily airborne and are difficult to remove in supplement manufacturing.  Additionally, the storage and transportation of plant materials can affect the amount of fungal contamination in the final finished product.  Therefore, it is nearly impossible for manufacturers to avoid mold spores.

The most common form of yeast that is harmful in large quantities in the body is Candida albicans.  It is pretty common to have an overgrowth of this type of yeast as a side-effect of fungal infections.

It is known that approximately 300 out of 1.5 million fungi present on Earth are hazardous to human health and may cause a variety of health conditions, from allergic reactions to life-threatening invasive infections.

One study on numerous dietary supplements found that 86.8% were contaminated with fungi (Ratajczak et al., 2020).  There are levels of specific mold types that are considered acceptable.  Anything above that threshold can be harmful.  In that same study, only five of the 122 samples contained a level over the acceptable point.

Approximately 300 out of 1.5 million known fungi on Earth are hazardous to human health. Fungi like aspergillus, Penicillium, fusarium and, Alternaria can produce mycotoxins.  Mycotoxins are toxic secondary metabolites produced by certain types of fungi capable of causing disease and even death.

Research has shown that these specific mycotoxins are often found in dietary supplements (Ratajczak et al., 2020):

  • Aflatoxins
  • Ochratoxin A
  • Zearalenone
  • Trichothecenes
  • Fumonisins

Not only are these mycotoxins often found in dietary supplements, but they are also quite dangerous as well.  One form of Aflatoxins is the strongest carcinogenic (cancer-causing) factor existing in nature( Ratajczak et al., 2020)!  Mycotoxins can have adverse effects on the urinary, reproductive, immune, and central nervous systems.

There are both long-term and short-term mycotoxin exposure side effects. Some of the more severe side effects of mold exposure can include:

  • Cancer
  • Kidney damage
  • Fetal development issues
  • Immune System Damage
  • Nausea
  • GI distress
  • Vomiting
  • Breathing issues
  • Skin Issues

One thing to consider is that if you have a sudden, unexplained, marked change in your health, mold could be the cause.

The side effects of ingesting or being exposed to more than acceptable amounts of mold are severe.  That is why it is crucial for supplement companies, especially those using plant-based ingredients, to have their products third-party tested.


You don’t want to take supplements with pathogens like salmonella, E. coli, S. aureus, or Enterobacteriaceae.  These pathogens are well-documented to be dangerous to humans.  It seems commonplace for food to be pulled from grocery stores and supply chains after discovering they are contaminated with one or the other bacteria types.

Symptoms of salmonella can include diarrhea, fever, chills, and abdominal pain.  For E. coli, the symptoms can range from stomach cramps to vomiting to bloody diarrhea.  Supplements with elevated levels of E. coli can be an indicator of poor raw materials and production hygiene.  S. aureus is a causative agent of food poisoning and, most commonly, skin infections.  The presence of S. aureus in dietary supplements can indicate poor hygiene practices by the manufacturer.

Residual Pesticides

There is a chance that a supplement you are currently taking contains residual pesticides.  The Clean Label Project found an alarming number of proteins to contain elevated levels of pesticides. Let’s discuss exactly how pesticides end up in the supplements you take.

Pesticides can include herbicides (weed combatants), insecticides (bug repellents), and fungicides (fungus killing/preventing).  They are used to protect crops and plants from getting eaten by bugs, overrun by weeds, and infected by fungi.  These plants and crops that have been sprayed with pesticides end up in your herbal and dietary supplements.  Although pesticides are great at protecting our crops, they are not so great for humans (and the environment, honestly).

The risk of pesticide exposure depends significantly on the type of pesticide that you are exposed to.  For example, a low level of exposure to a highly toxic pesticide may not be more dangerous than high-level exposure to a relatively low toxicity pesticide.


According to the EPA, the side effects of pesticides on the human body also depend on the type of pesticide they are exposed to.  Some of the health effects include:

  • skin irritation
  • eye irritation
  • nervous system disorders such as excessive twitching, weakness, and Incoordination
  • headache
  • nausea
  • dizziness
  • increased salivation, sweating, tearing, phlegm
  • cancer
  • hormone/endocrine issues

The EPA sets maximum allowable levels of pesticides to be used on plants to ensure the residual amounts are at a level that is safe to be exposed to.  Chances are if your supplement does contain some pesticides, they are not in overly large quantities.  However, supplement companies must test their products to be sure.  There is always a risk of having an unacceptable level of residual pesticides.

Why don’t all supplement company’s third-party test their products?

 The same reason that the vast majority of supplements are grossly under-dosed.  Money.  You have to pay a third-party lab to test your products, and a company should repeat testing every batch.  Additionally, some companies may not be confident in their results should they choose to test their products.

Even if a company does pay for third-party testing, this does not necessarily make their products high-quality.   You might read that a company uses third-party testing, but what are they testing for?  Just one thing or a multitude of things?

Also, what were the results?!  You CAN be third-party tested and still have less than stellar results.  Is the company bragging about third-party testing without making the results easily accessible?  This should be a red flag.  If the results are good, why not make them easily accessible to your customers?

Supplement companies aren’t even required to have third-party testing completed.  Many choose not to, due to the high cost.  Additionally, each batch of supplements should be third-party tested.  The cost of these repeated tests adds up.  Many supplement companies don’t want to pay for this.

What can you do to ensure safe supplementation?

I did not write this blog to scare you from supplements!  I just wanted to emphasize how important third-party testing is.  Not only do you want the supplements you take to be third-party tested, but you also want them to be done comprehensively.  When you have the knowledge of what to look for in a supplement, you are empowered.  Because the supplement industry is not strictly regulated, it is up to the buyer to be informed.

One thing to look for in a supplement is to make sure that the supplement manufacturer is an NSF-certified manufacturer.  You also want to ensure that their NSF listing shows that they are a GMP facility.  This certification means that the manufacturer has Good Manufacturing Processes.  GMP is a system that ensures products are consistently produced and controlled according to specific quality standards.  In essence, it is a facility that handles its products and manufactures supplements in a safe, controlled manner.

You might have to look into this a little further than looking at the label of the supplement.  Not all supplement companies manufacture their own supplements.  However, you should be able to find out relatively easily who manufactures their supplements.  Once you know that, you can see if they are an NSF-Certified and GMP facility.

Even though most people hate doing this, you should research the ingredients in the supplement you consider taking.  A high-quality supplement will only contain ingredients backed by peer-reviewed scientific studies.  If the science doesn’t support your supplement, it probably isn’t going to be very helpful.

This wouldn’t be a third-party testing blog if I didn’t recommend that you ensure any supplement you take is third-party tested.  Not only that, but you want that company to make their results easily accessed and presented in the manner of the actual results.  The supplement company should not change how the results are presented to be easier to read.

Re-wording and putting in a different format makes it so the results presented might not be the real results.  Anyone can put anything in a spreadsheet or document.  If the presented testing results aren’t the original results from the third-party testing company, you should be leery of them.

Ultraverse Supplements

We would be pretty big hypocrites if we wrote an entire article on third-party testing and didn’t talk about our products’ results.  All of our supplements are third-party tested.  If you visit our website, you can easily access all our third-party test results on each product.  We are obsessive and meticulous in our pursuit to include only evidence-based ingredients, scientifically relevant doses, and the highest quality supplements possible.

Additionally, we want to ensure that our supplements are safe.  I will let you in on a secret: we, the owners of Ultraverse Supplements, take these supplements.  Why would we want to sell a product we wouldn’t be safe taking?

We feel like our third-party tests reflect that.

In the interest of being fully transparent, here are the results for both our products:


Accuracy & Potency

Purity (mold, yeast, bacteria)

Heavy Metals

Residual Pesticides


Accuracy & Potency

Purity (mold, yeast, bacteria)

Heavy Metals

Residual Pesticides

We are pretty proud of our test results.  We believe that these results reflect our determination to give you the best products possible.  So, next time you are researching a supplement to add to your regimen, make sure you research their third-party testing results.  If you can’t find them easily, or if their information is vague, you might want to rethink buying that supplement!


Abdulla, N. M., Adam, B., Blair, I., & Oulhaj, A. (2019). Heavy metal content of herbal health supplement products in dubai – UAE: A cross-sectional study. BMC Complementary and Alternative Medicine, 19(1), 276. doi:10.1186/s12906-019-2693-3

Jaishankar, M., Tseten, T., Anbalagan, N., Mathew, B. B., & Beeregowda, K. N. (2014). Toxicity, mechanism and health effects of some heavy metals. Interdisciplinary Toxicology, 7(2), 60-72. doi:10.2478/intox-2014-0009

Ratajczak, M., Kaminska, D., Światły-Błaszkiewicz, A., & Matysiak, J. (2020). Quality of dietary supplements containing plant-derived ingredients reconsidered by microbiological approach. International Journal of Environmental Research and Public Health, 17(18), 6837. doi:10.3390/ijerph17186837

2 thoughts on “Third-Party Testing for Supplements: Everything You Need to Know

  1. Casey Hammond says:

    Thanks, Anna! We strive to be as transparent with our products as possible, and we feel that part of that is making our third-party testing results visible and easily accessible.

  2. Anna says:

    This is a REALLY helpful article, thank you! However, I don’t think I’ve ever seen a company post testing results like you do….even if the products are said to be certified and third party tested. And good point about the fact that being tested doesn’t say anything about the results of the test. There’s a fish oil I’ve verified has been third party tested but there’s no info about it on the product page. I emailed them and they gave me the name of their testing company, ISURA (in Canada). The way they wrote the info in the email doesn’t make it clear to me that they’ve been testing for heavy metals which is a main concern with fish oil. They write:
    “Some of the product certification services include:
    • Non-GMO and organically grown
    • Product potency and integrity
    • Pesticide-free and solvent-free

    …and then further on it says “At X company, we are committed to providing you with the finest natural products for your health….Each and every ingredient is tested for identification, purity, heavy metals, pesticides and other contaminants in accordance with NNHPD, Food and Drug Administration (FDA) and United States Pharmacopoeia (USP) requirements. Our laboratories also test finished products post-manufacturing for contaminants and impurities as well as numerous physical and potency related tests, such as disintegration, dissolution, weight variation, microbial contamination, heavy metals and pesticides.”

    Since heavy metals wasn’t in initial list I’m thinking they get the ISURA to test the three things they listed but they do their own testing for metals. Otherwise, why would they word it that way. It does sound like they are very conscientious though. So hard to know what to think. I guess it would be OK if the company does their own testing as long as they’re honest.

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