Independent Testing & Certificates of Analysis

"Third-party tested" and "certificate of analysis" (CoA) are phrases that make a product sound checked. Testing is useful, but how useful depends on what was tested, by what method, on which batch, and who is making the statement. This page explains the terms for adaptogen products such as ashwagandha (Withania somnifera), rhodiola (Rhodiola rosea) and ginseng (Panax ginseng), using regulations and published studies. It does not rank programs or name products. For the general guide to certification programs, see Quality testing and certifications.

Who is responsible for quality in the US

• The FDA does not approve dietary supplements for safety and effectiveness before they are sold. Companies must make sure products meet safety standards. [1]
• NIH says manufacturers are required to produce supplements in a quality manner, ensure they do not contain contaminants or impurities, and label them accurately, but the rules are less strict than for prescription or over-the-counter drugs. [2]
• The FDA periodically inspects supplement manufacturing facilities to verify that companies meet manufacturing and labeling requirements. [1]
• Under the manufacturing rule, a company must conduct at least one appropriate test or examination to verify the identity of any component that is a dietary ingredient, unless FDA exempts it after a petition. [3]

So some testing is required of makers. What is not described in the sources we read is how any one company's results are shared with buyers.

What a certificate of analysis is

A review of botanical extracts describes certificates of analysis as the documents that report the results of the scientifically valid methods used to confirm a botanical extract ingredient meets its specifications. [4] The same review warns that CoAs routinely include additional information, such as plant-to-extract ratios, that cannot be verified by analysis. [4] So a CoA can mix measured results with descriptions.

Questions the sources we read do not answer: whether a CoA refers to the raw ingredient or the finished capsule in a given product, whether the lab is independent, and whether it covers the batch you hold. Those are the questions to put to a seller. See extract ratios.

What "third-party" testing means

In general terms, a party outside the maker checks something about the product, and the label may then say so. A pharmacy journal paper about probiotics says that using a third party to verify compliance with manufacturing and label accuracy adds assurance, and that pharmacists should require CoAs for products used in at-risk patients. [5] That paper is about probiotics and reflects the authors' view, so it does not show how any adaptogen program performs.

NIH cautions that a maker's use of "standardized," "verified" or "certified" does not necessarily guarantee quality or consistency. [2] The same applies to "tested" without detail. See also third-party testing and what it shows.

Which tests exist, and their limits

What the product studies suggest about trusting a document

Published product studies found mismatches in some adaptogen products: in a 2025 analysis of 13 rhodiola products, nearly 60% did not contain the declared amount of rhodiola root or its characteristic markers, and the authors argue that rigorous control and standardization are crucial. [9] In a 2026 study, only 10 of 25 ashwagandha products met both British and US pharmacopoeia standards. [7] These are small studies that tested products at one time. They do not show the share of all adaptogen products that fail, and they do not tell you which products have good paperwork.

Proper evidence not found: we searched PubMed for studies comparing certificates of analysis or third-party seals with independent laboratory results for adaptogen supplements, and found none. A narrative review of adaptogen regulation notes that the quality requirements for pharmaceuticals and for botanical dietary supplements differ. [10]

Questions worth asking, and who can help

• Does the seller state the species, plant part and extract type? (See reading an adaptogen label.)
• Is there a document for the specific batch, and who ran the tests?
• Does it test for contaminants as well as markers? (See contamination and adulteration.)

A pharmacist can help read a label or a CoA against your medicines. Testing for purity does not make a product safe for you: cautions with medicines, pregnancy, thyroid or liver conditions and surgery still apply. See medicine interactions and adaptogen safety.