Selenium is much less expensive than mushroom capsules, and is also high in inexpensive, nutritional yeast.
Is selenium mushroom’s main, magic, health ingredient? This has been my thought for many years. I am not saying this is the case, and I’m not a doctor giving advice (for the record), but mushrooms are definitely high in selenium — which American soils are often low in.
This is a possibility; food for thought.
Mushrooms are a good source of the minerals potassium, selenium, copper and phosphorus. Mushrooms contain more potassium than most other vegetables and fruits. This mineral can have a positive effect in lowering blood pressure. Selenium has anti-oxidant properties, rendering harmful free radicals safe and is therefore implicated as an anti-cancer agent. (source)
That said, another good characteristic of turkey tail and many other mushrooms like shiitake is that they can also accumulate selenium from the environment. When mercury meets selenium, they form a bimolecular unit that is totally non-toxic. This is why, whenever I eat fish, I like to have soup with organic shiitake — or better yet, add turkey tails! (source)