Quick answer

Turkey tail is a mushroom whose extracts, PSK and PSP, have been studied mainly in people under medical care. In healthy people the research is a handful of small studies lasting 4 days to 4 months, none testing turkey tail alone against a health outcome, so this page makes no benefit claim.^1,2,3

Key facts

A Cochrane review of seven controlled trials covered 1,569 people under medical care in Japan and China who took turkey tail extract.¹
In 12 healthy adults, 3.6 g a day of the PSP extract for 14 days did not change CYP3A4, a liver enzyme that clears many medicines.⁴
Healthy adults took up to 12 g a day of a turkey tail blend for four days with no adverse events reported.²
Rats showed no toxic effects from a turkey tail mycelium powder at up to 2,000 mg per kg a day.⁵

What turkey tail is

Turkey tail is the common name for the mushroom Trametes versicolor. It is also sold as Coriolus versicolor, and in Chinese medicine it is called yun zhi.^1,3

PSK (polysaccharide-K, also called Krestin) and PSP (polysaccharopeptide) are concentrated extracts of turkey tail, and most of the human studies cited here used one or the other.^1,4,6

Some turkey tail products are made from mycelium grown on grain such as oats. One trial used freeze-dried mycelium powder in 500 mg capsules.^5,7

Our own product lists an extract of the fruiting body, the visible mushroom. Extracts, mycelium powders and fruiting body products are made differently, and a result from one cannot be assumed for another.

What the evidence shows

No benefit claim for turkey tail passes our evidence rules. The best-known research gave its extracts to people under medical care, and those results cannot be carried over to healthy people. What has been studied in healthy people is set out below, and none of it tested turkey tail on its own against a health outcome.

A 2022 Cochrane review covered seven controlled trials in which 1,569 people under medical care in Japan and China took turkey tail extract, mostly PSK, alongside their usual care.¹

In a small randomized trial in healthy volunteers, the PSP extract changed the mix of bacteria in stool samples, a pattern the authors described as prebiotic. Each person's starting bacteria mattered more than the extract, and no health outcome was measured.⁶

We could read only the summary of that trial, which does not give the amount of PSP used, and the full paper is behind a paywall.⁶

In the four-month trial of turkey tail with danshen, some immune cell measures changed compared with placebo, but the effect of turkey tail alone cannot be separated from that of the herb.³

Changes in gut bacteria or immune cell counts are signals worth studying, not proof that a person is healthier. Until a trial in healthy people tests turkey tail on its own against an outcome that matters to them, there is nothing to grade.

Amounts in studies

In a 14-day study in 12 healthy adults, the PSP extract was taken as 1.2 g three times a day with meals, 3.6 g a day in all.⁴

A four-month trial in 100 healthy adults gave turkey tail at 50 mg per kg of body weight a day, together with the herb danshen at 20 mg per kg.³

In a 2026 trial, 52 adults took 12 g a day of a mycelium blend of turkey tail and another mushroom, Fomitopsis officinalis, for four days around a vaccine dose.²

There is no standard dose. The dosage guide sets these amounts side by side and works out what the weight-based amount means for a typical adult.

What's in ours

In our Mushroom Complex, turkey tail is one of six mushrooms sharing the proprietary blend shown above. The label gives only the blend's total, not the turkey tail share, and even the whole blend is a small fraction of the 3.6 g of extract a day used in the healthy-adult study.⁴

Side effects, medicines and who should ask first

In a six-week trial of 3, 6 or 9 g a day of mycelium powder in nine women who had just finished radiotherapy for breast cancer, seven of the nine reported events were mild, among them heartburn, constipation and palpitations. Nausea and stomach upset were not reported, and the one severe event was judged unlikely to be related.⁷

In seven trials of turkey tail extract given with chemotherapy for bowel cancer, reviewers could not tell which side effects came from the extract and which from the chemotherapy.¹

No upper limit has been set for turkey tail. The highest amounts reported in people are 9 g a day of mycelium powder for six weeks and 12 g a day of a mushroom blend for four days. Use beyond four months has been studied only in people under cancer care.^1,2,3,7

In 12 healthy adults, 3.6 g a day of the PSP extract for 14 days did not change the activity of CYP3A4, a liver enzyme that clears many medicines. Other drug-handling enzymes were not tested.⁴

That enzyme test was small and short and checked a single enzyme, so it does not show that turkey tail leaves all medicines alone. If you take warfarin, its label asks for more frequent INR checks whenever an herbal product is started or stopped.^4,8

Much of the turkey tail research comes from people being treated for cancer, often given the extract alongside chemotherapy. If that is you, ask your cancer team before taking it, because they need to know about every supplement you use.¹

In March 2026 the FDA warned a seller of turkey tail, chaga and red reishi extracts that citing research on illness to market them made the products unapproved new drugs.⁹

Ask first if you take a blood thinner or an antiplatelet medicine
Ask first if you take medicines that suppress the immune system
Ask first if you are pregnant or breastfeeding
Avoid it if you are allergic to mushrooms or molds

Questions people ask

What does turkey tail mushroom do for the body?

In healthy people, no study has shown that it changes health. Small studies found a shift in gut bacteria with one extract, and changes in immune cell counts when it was combined with an herb, but none tested turkey tail alone for an effect on health.^3,6

What is the best way to take turkey tail mushroom?

We found no study that compared forms or schedules. The studies in healthy adults used capsules taken three times a day, one of them with meals, and the amounts varied widely.^2,4

Are there turkey tail benefits for hair?

We found no study of turkey tail and hair in people.

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Sources

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.