Trametes versicolor – also known as Coriolus versicolor and Polyporus versicolor – is a common polypore mushroom found throughout the world. Owing to its shape being similar to that of a wild turkey's tail feathers, T. versicolor is most commonly referred to as turkey tail.

Although polysaccharide-K, an extract of T. versicolor, is approved in Japan as an adjuvant therapy in cancer treatment, it is not approved in the United States for treatment of cancer or any clinical condition. Extracts of turkey tail or the mushroom itself are commonly marketed as a dietary supplement for various health benefits, but there is no good scientific evidence for safety or effectiveness, and quality can vary due to inconsistent processing and labeling.

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