Turkey Tail

Cancer care comes first. A supplement is not a cancer treatment. If you are in cancer care, tell your oncology team about any turkey tail product before you start, because they know your treatment plan. The US Food and Drug Administration (FDA) has not approved coriolus extracts as additional cancer treatments, according to Memorial Sloan Kettering Cancer Center (MSK). [1] MSK also advises people who are pregnant or breastfeeding to avoid coriolus until safety data are available. [1] See Turkey tail, PSK and cancer care and what to tell your care team.

What it is

Turkey tail is Trametes versicolor (L.) Lloyd, the accepted name; the older name Coriolus versicolor is a synonym, and both appear on labels and in studies. [2] The National Cancer Institute (NCI) summary describes it as a woody bracket fungus that grows on dead logs worldwide, called Yun Zhi in traditional Chinese medicine and Kawaratake in Japan, and says that many other Trametes species are difficult to distinguish from it. [3] That is why this guide gives no identification help: wild mushrooms should never be eaten on the strength of a description or photo. For any wild mushroom that was eaten, call Poison Help at 1-800-222-1222 in the US.

PSK is a medicine in Japan; supplements are different

• PSK (krestin) is a proprietary extract. NCI says a purified hot water extract of cultivated mycelium has been used in Japan as an adjunct in cancer treatment, that PSK is an approved mushroom product there, has been used since the mid-1970s, and has a well-established safety record with few adverse events reported. [3]
• PSP is another extract from T. versicolor, produced in China. [3]
• Supplements in other countries are different products. MSK says many over-the-counter products are not standardized and that it is unclear whether PSK, PSP and other extracts have comparable effects. [1]

Do not assume a capsule matches the product tested in a trial. See PSK, PSP and lentinan.

Traditional use

Traditional use only, not proof. The NCI summary says the fungus has been used in traditional Chinese medicine for many years to treat pulmonary diseases. [3] MSK adds that it is used in traditional Chinese medicine as a tonic. [1]

What research shows

A 2023 systematic review of mushroom studies in cancer care, which included 39 clinical studies, concluded the evidence is inconclusive for recommending routine use; many studies were small or observational. [8]

Official statements

• NCI (PDQ, updated 2024): PSK is approved for cancer treatment in Japan; the FDA has not approved medicinal mushrooms to treat cancer or any other condition. [3]
• MSK: the FDA has not approved coriolus extracts as additional cancer treatments. [1]

Lab data and chemistry

Two things are kept apart here: what laboratories have reported finding in turkey tail, and what a food or supplement actually delivers. Neither is a health claim.

A. What the laboratory literature reports in this mushroom. Wikidata, which collects compound-in-species statements from published studies (the LOTUS project), lists 20 compounds for Trametes versicolor. [9] A listing means "reported in at least one study of this species", not "present in every product". The list is short and does not include the large protein-bound sugars (PSK and PSP), because those are polymers rather than single molecules; they are described from a review. [10] The identity codes below are Wikidata item numbers (Q) and ChEBI numbers, taken from the Wikidata data. [9]

Ergothioneine, beta-glucan as a single measured number and triterpenes are not on the Wikidata list for this species, so nothing is claimed about them.

B. Measured values. USDA FoodData Central has no turkey tail entry (checked in the project's USDA file), so there are no USDA values. [12] The only open measured nutrition values we found are from one 2026 paper on fresh fruiting bodies bought or collected in Nigeria, dried at 40 degrees C and analysed by standard (AOAC) methods; the values below are per 100 g of dried powder, mean of 2 determinations. [11]

Cautions about this paper: it has only two determinations per value; the text and its own table disagree on potassium (the text gives ten times the table value, so we show the table); and the sample source and identification are described only briefly. Treat it as a rough indication, not a reference. [11] One other 2024 paper measured beta-glucan in a Trametes strain, but it identified the strain only as Trametes sp. (close to T. flavida), not T. versicolor, so we do not use its numbers. [13]

C. What the numbers do and do not mean

• Amounts in a mushroom vary with strain, growing material, harvest, drying and extraction method, so one paper is one sample, not "the" value.


• Turkey tail is described as a woody bracket fungus [3]; the table describes a dried powder and says little about what a person would take in from a product.


• A compound found in the laboratory does not show a health effect. PSK was studied as a purified extract; a capsule of ground mushroom or of mycelium on grain is a different product. See fruiting body versus mycelium and mycelium on grain.


• "Standardised to polysaccharides" or "beta-glucan" depends on the test used; PSK and PSP also carry alpha-linked glucose units and a protein part, so they are not simple beta-glucans. [10] See beta-glucans versus polysaccharides.


• PSP is described as roughly 90% polysaccharide and 10% peptide, with a molecular size near 100 kDa for PSK and PSP; this is a property of the purified extract. [10]