Birch Mazegill (Lenzites betulina)
A mushroom that looks like a turkey tail bracket but has true gills instead of pores underneath its cap. A handful of real laboratory studies (anticancer and antioxidant, in vitro), zero clinical studies in humans.
Table of contents
TL;DR
A mushroom that looks like a turkey tail bracket but has true gills instead of pores underneath its cap. A handful of real laboratory studies (anticancer and antioxidant, in vitro), zero clinical studies in humans.
- →In an in vitro study, an ethanolic extract showed strong cytotoxic activity against a breast cancer cell line, plus moderate antimicrobial activity — laboratory results only
| Latin name | Lenzites betulina (syn. Trametes betulina) |
|---|---|
| Family | Polyporaceae |
| Active compounds | Unspecified compounds in the ethanolic extract; antioxidant compounds in selenium-enriched mycelium |
| Form | None — not available as a dietary supplement |
| Research level | Early: 2 in vitro studies, 0 animal or human studies |
| Interactions | None described |
| Status | Common species, inedible, no protected status |
Understand
Overview
The birch mazegill (Lenzites betulina, classified by some as Trametes betulina) is a mushroom whose upper surface deceptively resembles turkey tail brackets, but which has true, radiating gills instead of pores. It grows commonly on dead hardwood throughout Poland.
Like the Trametes species described elsewhere in this knowledge base, the birch mazegill is not present on the Western supplement market. However, a few genuine laboratory papers exist on its anticancer and antioxidant effects.
Who does this actually help, and who doesn't it help? No one, as a supportive therapy — especially not people with cancer, who might mistakenly interpret the extract's strong cytotoxic effect against breast cancer cell lines as a signal of real efficacy. This is a typical result of an early in vitro screen, without even confirmation in animals. The entry has real value for people following research directions into mushrooms as a source of new anticancer compounds.
Where it's found
Lenzites betulina occurs commonly throughout Poland and more broadly across the temperate zone of the Northern Hemisphere as a saprotroph decomposing dead hardwood. Its fruiting bodies are hard, corky, and persist on the substrate for many months.
Mechanism of action
Compounds showing strong cytotoxic activity against breast cancer cell lines in vitro were isolated from an ethanolic extract of the fruiting body. Mycelium enriched with selenium showed enhanced antioxidant and cytostatic effects.
The study does not specify exactly which compounds in the ethanolic extract account for the cytotoxicity — the effect of the whole extract was described, not that of a single isolated molecule. A second study shows that the effect isn't constant: selenium-enriched mycelium showed a stronger effect than standard mycelium, suggesting that part of the activity may depend on the mushroom's interaction with trace elements in its substrate.
Cytotoxicity against breast cancer cells (in vitro)
An ethanolic extract of the fruiting body showed strong cytotoxic activity against the MDA-MB-231 cell line under laboratory conditions.
Enhanced effect via selenium enrichment
Mycelium cultured with added selenium showed a stronger antioxidant and cytostatic effect than unenriched mycelium.
Moderate antimicrobial activity
The same ethanolic extract also showed moderate activity against the tested bacteria and fungi.
Evidence: early-stage — based on 2 studies in this database.
Benefits
Forms & variants
Birch Mazegill (Lenzites betulina) comes in several forms that differ in bioavailability and use case — the form you pick genuinely matters for how effective the supplementation is.
Wild fruiting body
A hard, corky, inedible fruiting body.
Best for: Mycological observation
Practice
Frequently asked questions
The underside of the fruiting body settles it: the birch mazegill has true, radiating gills, while turkey tail brackets have fine pores.
Dosage & timing
Typical dose
Not established — not marketed as a dietary supplement
Form
Not applicable
Despite promising in vitro results, there is no basis for extrapolating them to efficacy or safe dosing in humans.
Best times to take it
- Not applicable
Safety
Side effects & contraindications
Possible side effects
No data on safety of use in humans
Contraindications
Not applicable — no products on the market and no clinical data
Interactions
No interactions described
Is it worth taking?
Who it's for
- In an in vitro study, an ethanolic extract showed strong cytotoxic activity against a breast cancer cell line, plus moderate antimicrobial activity — laboratory results only
Not for
- Not applicable — no products on the market and no clinical data
Evidence
Worth knowing
Unlike turkey tail brackets, the birch mazegill has true gills, not pores, underneath its cap.
Some mycologists classify this species as Trametes betulina.
Studies
An ethanolic extract of the fruiting body showed strong cytotoxic activity against the MDA-MB-231 breast cancer cell line.
Liu K, Wang JL, Zhao L, Wang Q, International Journal of Medicinal Mushrooms, 2014
Anticancer and Antimicrobial Activities and Chemical Composition of the Birch Mazegill Mushroom Lenzites betulina
Early-stage evidenceLiu K, Wang JL, Zhao L, Wang Q · International Journal of Medicinal Mushrooms · 2014
An ethanolic extract showed strong cytotoxic activity against the MDA-MB-231 breast cancer cell line and moderate activity against bacteria and fungi.
View studyEffect of Selenium Enrichment of Lenzites betulinus and Trametes hirsuta Mycelia on Antioxidant, Antifungal and Cytostatics Potential
Early-stage evidenceMilovanovic I, et al. · Current Pharmaceutical Biotechnology · 2015
Selenium-enriched mycelium showed stronger antioxidant and cytotoxic effects in vitro than unenriched mycelium.
View studySources & bibliography
Citations are illustrative for this demo version and require full bibliographic verification by the editorial team before production publication.
Compare with similar entries
About the authors of this entry
Author
dr Piotr ZielińskiEndocrinologist
Piotr reviews content on hormones, metabolic health and supplement pharmacology.
131 publications on this site
Medical review
Julia WiśniewskaEditor, Neurohacking & Sleep
Julia writes about nootropics, chronobiology and recovery protocols.
45 publications on this site
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Comments (2)
- KW
Kasia W. 2 weeks ago
Very clearly explained, especially the interactions section — I hadn't seen it laid out this well anywhere else.
- MT
Marek T. a month ago
Are you planning to update this with the newest study from this year? I saw an interesting meta-analysis.