Quality Guide · Updated March 2026
How to Read a COA for Mushroom Supplements
A Certificate of Analysis is the only proof that a mushroom supplement actually contains what the label says. Here's exactly what to look for — and what red flags mean.
Board-Certified Physician · Medical Reviewer · Published February 11, 2026
What Is a COA?
A Certificate of Analysis (COA) is a document issued by an independent analytical laboratory that verifies the composition, purity, and safety of a supplement product. It's the only independent verification that a brand's label claims are accurate.
Why This Matters for Mushrooms Specifically
The mushroom supplement industry has a documented quality problem. A 2017 analysis by the Usefully Mushrooms research group found that many products claiming to contain "medicinal mushrooms" were primarily composed of grain starch from myceliated substrates — with negligible actual mushroom content. Without a COA, you have no way to know if you're paying for mushrooms or oats.
✓ What a COA Confirms
- • Mushroom species identity (DNA verification)
- • Beta-glucan content (actual bioactive compounds)
- • Heavy metals below safety limits
- • No harmful pesticides or mycotoxins
- • Microbial safety (no E. coli, Salmonella)
✗ What a COA Doesn't Guarantee
- • Clinical efficacy for specific health claims
- • Bioavailability (how much absorbs)
- • Efficacy of extraction method
- • Consistency across all future batches
- • Results if the COA is outdated (>2 years)
The 5 Key Sections to Check
Lab Accreditation
The lab issuing the COA must be an independent, accredited third party — not the brand's own internal lab. Look for ISO/IEC 17025 accreditation or state-licensed analytical lab credentials in the footer of the document.
🚩 Red Flag: COA issued by "Brand Name Quality Control Lab" — that's an in-house lab, not third-party.
Identity / Species Verification
The COA should confirm that the mushroom species claimed (e.g., Hericium erinaceus for Lion's Mane) are actually present. The gold standard is ITS (Internal Transcribed Spacer) DNA barcoding which can identify species at the molecular level.
Look for: "Identity — PASS" and the Latin binomial species name in the test results.
Beta-Glucan Content
This is the most important number for immune and health benefits. A quality fruiting body extract should show 15–40% beta-glucans by dry weight. Products with myceliated grain biomass often show <5% beta-glucans and >40% starch.
| Beta-Glucan % | What It Means | Quality |
|---|---|---|
| 25–40% | Premium fruiting body extract | Excellent |
| 15–25% | Good quality extract | Good |
| 5–15% | Mixed fruiting body/mycelium | Marginal |
| <5% | Likely myceliated grain biomass | Poor |
Heavy Metals Panel
Mushrooms are bioaccumulators — they absorb heavy metals from their growing substrate. A complete panel should test for Lead (Pb), Mercury (Hg), Arsenic (As), and Cadmium (Cd). Results should fall below USP <232> limits.
Lead
≤10 ppm
Mercury
≤3 ppm
Arsenic
≤15 ppm
Cadmium
≤5 ppm
Lot Number & Date
Match the lot number on the COA to the lot number printed on your bottle or packaging. A COA for a different batch doesn't verify your product. Check the analysis date — COAs older than 2 years may not reflect current production quality.
💡 Tip: Email the brand asking for the COA for the specific lot number on your package. A legitimate brand will respond within 24–48 hours.
Beta-Glucans vs Polysaccharides: Not the Same Thing
⚠️ Common Misleading Claim
Many supplement labels say "high in polysaccharides" or show "polysaccharide %" on a COA. This is misleading. Starch is a polysaccharide. Myceliated grain biomass (the cheap filler) is extremely high in starch polysaccharides — which have no immune benefit. Only beta-glucan polysaccharides (specifically beta-1,3/1,6-glucans from mushroom cell walls) deliver the benefits you want.
✓ BETA-GLUCANS
- • Found in mushroom cell walls (chitin matrix)
- • Binds to dectin-1 receptors on immune cells
- • Activates NK cells, macrophages
- • Acts as prebiotic for gut microbiome
- • What COA should specifically test for
✗ STARCH POLYSACCHARIDES
- • From grain (rice, oats, barley substrate)
- • Digested as a simple carbohydrate
- • No immune modulating effects
- • Common in myceliated grain biomass
- • Often shown as high "polysaccharide %" on inferior COAs
COA Red Flags at a Glance
COA tests only "total polysaccharides" — not beta-glucans specifically
This is the most common sleight of hand in the industry. Always ask for beta-glucan-specific results.
High starch content (>15%) alongside high "polysaccharides"
Real mushroom fruiting bodies have very low starch. High starch = myceliated grain in the mix.
COA dated more than 2 years ago
Production quality can change. An old COA doesn't represent current batches.
Brand refuses to share COA or says it's "proprietary"
Lab test results aren't a trade secret. If a brand won't share their COA, that tells you everything.
No heavy metals panel in the COA
Mushrooms bioaccumulate heavy metals from soil and substrate. A COA without heavy metals testing is incomplete.
Trusted Testing Labs for Mushroom Supplements
Eurofins
ISO/IEC 17025 Accredited
The world's largest food and supplement testing network. Gold standard for identity testing and contaminant screening. Multiple facilities worldwide.
Alkemist Labs
ISO/IEC 17025 Accredited
Specialized in botanical identity testing. Excellent for mushroom species DNA verification and TLC/HPTLC fingerprinting of extracts.
NSF International
Third-Party Certification Body
NSF Certified for Sport certification means athletes can trust the product is free from banned substances and accurately labeled.
Intertek
ISO/IEC 17025 Accredited
Full-service testing including pesticide residue, mycotoxins, microbiological safety, and active compound quantification.
Frequently Asked Questions
Czym jest COA i dlaczego powinienem go sprawdzać przy suplementach grzybowych?
Certyfikat Analizy (COA) to dokument z niezależnego laboratorium zewnętrznego potwierdzający, co faktycznie znajduje się w suplemencie — i czego w nim nie ma. Bez COA wszelkie twierdzenia na etykiecie suplementu grzybowego są niezweryfikowane. COA powinien potwierdzać: (1) deklarowane gatunki grzybów są obecne w podanej ilości, (2) zawartość beta-glukanów jest rzeczywista (nie tylko skrobia), (3) produkt jest wolny od metali ciężkich jak ołów, rtęć, arsen i kadm, (4) brak szkodliwych drobnoustrojów lub pestycydów.
Jaki procent beta-glukanów powinien mieć dobry ekstrakt grzybowy?
Wysokiej jakości ekstrakt z owocnika z ekstrakcji gorącą wodą powinien zawierać 15–40% beta-glukanów w suchej masie. Cokolwiek poniżej 10% to czerwona flaga — prawdopodobnie zawiera znaczną ilość skrobi z grzybni na zbożu. Najlepsze produkty (jak Real Mushrooms) reklamują >25% beta-glukanów i publikują wyniki COA na dowód. Uwaga: 'polisacharydy' na etykiecie to NIE to samo co beta-glukany — skrobia też jest polisacharydem, ale nie ma korzyści immunologicznych.
Czy mogę ufać COA na stronie marki?
Częściowo. COA na stronie marki jest lepszy niż brak, ale idealnie chcesz zweryfikować: (1) laboratorium, które wydało COA, jest prawdziwym akredytowanym laboratorium zewnętrznym (nie laboratorium wewnętrznym), (2) COA zawiera numer partii odpowiadający partii, którą kupujesz, (3) COA jest datowane w ciągu ostatnich 12–24 miesięcy. Laboratoria akredytowane ISO/IEC 17025 to złoty standard — muszą spełniać międzynarodowe standardy dokładności testów.