In 2019 the FDA tested 30 kratom products pulled from a range of sellers and found lead and nickel in all of them, several at levels above what the agency considers acceptable for daily oral intake. The products came from ordinary online shops and storefronts. Nothing on the packaging would have told you.
That’s the problem with buying plants in a bag. Ashwagandha, , mushroom extracts, turmeric, kratom: they’re all agricultural products first, and what ends up in the jar depends on soil, harvest, drying, storage, and whether anyone bothered to check. The NIH Office of Dietary Supplements is straight forward about the regulatory side too: the FDA doesn’t evaluate whether a supplement works before it goes on sale, so the burden of vetting falls on you.
These are the eight questions I’d put to any seller before ordering. I’ve used kratom as the running example because it’s the category where the answers matter most, but every question applies to the rest.
1. Is every batch third-party tested?
Not “do you test.” Every batch. Plants vary from harvest to harvest, and a lab result from last spring says nothing about the bag shipping this week.
“Third-party” matters as well. An in-house test is better than nothing, but an independent, accredited lab has no stake in the result. A good answer sounds like “yes, each lot goes to an outside lab before release.” A bad answer is a vague paragraph about the company’s “commitment to quality.”
2. Can I see the actual certificate of analysis?
A certificate of analysis (CoA) is the lab’s report for a specific batch. It’s a document with a lab name, a sample ID, a date, and a table of results. It’s not a badge that says “Lab Tested” on the product page.
Ask for the CoA matching the lot number on the bag you’d receive. Serious vendors put this behind a QR code on the package or a lookup page on the site. If the vendor can’t produce one, or sends a generic “sample” certificate with no lot number, that tells you what you need to know.
3. Does the label state how much of the active compound is in it?
For botanicals with a known active constituent, the label should say how much. Curcumin percentage on turmeric extract. Mitragynine percentage on kratom.
This is where a lot of kratom products fall apart. Mitragynine content in commercial products varies several-fold between samples, so a bag labeled only “Green Maeng Da, 100g” leaves you guessing at the one number that actually matters. If you’re going to buy kratom that lists mitragynine content on the label, and confirms it with a batch-specific CoA, you’re already ahead of most of the market.
There’s a darker version of this issue. A study published in Journal of Medical Toxicology found multiple packaged kratom products with concentrations of 7-hydroxymitragynine far above what occurs in natural leaf, which the authors concluded was likely deliberate adulteration. A vendor that publishes alkaloid results per batch makes that kind of spiking visible. One that doesn’t, doesn’t.
4. What’s in it besides the plant?
Read the ingredient line, not the marketing copy. Common additions include:
- Flow agents and fillers such as rice flour or maltodextrin
- Artificial colors, common in gummies and some capsules
- Gelatin or vegetable-cellulose capsule shells (fine, but worth knowing)
- Flavorings and sweeteners in drinkable or chewable formats
- Undisclosed “proprietary blends” that hide the ratio of ingredients
None of these are automatically disqualifying. But a plant product with a five-item ingredient list where the plant is item three is a different thing from a bag of powdered leaf.
5. Where and how is it made?
You don’t need a factory tour. You need to know the country of manufacture, whether the facility handles its own processing or contracts it out, and whether any recognized manufacturing standard applies. A seller that names its facility and location is easier to trust than one that describes its supply chain in adjectives.
6. How is it stored and how fresh is it?
Alkaloids and other active compounds degrade with heat, light, and oxygen. Powdered leaf that sat in a warm warehouse for a year isn’t the same product it was at packaging. Look for a packaging or best-by date on the bag, opaque or resealable packaging, and some statement about storage. If there’s no date at all, ask how long the vendor’s inventory typically sits.
7. What happens if I don’t like it?
A return policy is a signal, not only a convenience. Vendors that offer a satisfaction guarantee on an opened product are betting that most people won’t use it, which means they’re confident in what they ship. Thirty days is a common window for botanicals. No returns on opened product is defensible for some categories, but combined with weak answers to questions 1 through 3 it starts to look like a pattern.
8. Are the claims on the page reasonable?
This one’s the fastest screen. Botanical supplements aren’t approved to treat, cure, or prevent anything, and a seller who says otherwise is either uninformed or willing to say whatever sells. Language to watch for:
- Any named medical condition presented as something the product addresses
- “Clinically proven,” “doctor recommended,” or similar phrasing with no citation
- Guaranteed results or effects described as if they were universal
- Comparisons to prescription medications
Vendors who know their category talk about product quality, testing, and format. They describe what customers tend to choose and why. They don’t promise outcomes, because they can’t.
Red flags and green flags at a glance
Red flags:
- No lot number on packaging
- “Lab tested” badge with no downloadable report
- No mention of heavy metals or microbial testing anywhere
- Medical claims in product descriptions
- No physical address or contact information
Green flags:
- Batch-specific CoA available by QR code or lookup page
- Active-compound content printed on the label
- Ingredient list that’s mostly the plant
- Clear return window on opened product
- Facility location and testing regimen described in plain terms
How to read a CoA in 60 seconds
You don’t need a chemistry background. Scan for four sections:
- Identity confirms the sample is the plant on the label
- Active compound (mitragynine, curcumin, and so on) gives the measured percentage or milligram amount
- Heavy metals lists lead, arsenic, cadmium, and mercury against a limit, usually in parts per million; you want “pass” or a value below the limit on each line
- Microbial lists total aerobic count, yeast and mold, E. coli, and salmonella; “not detected” or “pass” is what you’re after
Confirm the lot number on the CoA matches the lot number on the bag. Check the date. That’s it.
Pull up the certificate for the last supplement you bought. If you can find it in under a minute, you’re shopping with the right vendor. If you can’t find it at all, you’ve learned something worth knowing before the next order.