Source of fungal polysaccharides that help support the immune system. Source of antioxidants that protect against oxidative and radiation damage. 

The aptly named 'king of mushrooms' packs a complex of sugars, triterpenoids, and antioxidants (including melanin),  that have been shown to help the immune system against viruses, radiation and oxidative damage and seem to have a protective impact against them.

Residents of Siberia and Indigenous people of North America have foraged wild Chaga for centuries for its various medicinal benefits. The name “Chaga” is derived from Russian, but the fungus has many names, including posahkan (Cree), shkitaagan (Anishinaabemowin), and mii’hlw and tiiuxw (Gitskan).