Chaga

Chaga is a fungus rich in polysaccharides, betulinic acid, and melanin. In vitro studies show antioxidant and immunomodulatory activity, but there are virtually no published human RCTs. Most evidence is preclinical (animal/cell studies). Popular in traditional Siberian and Northern European medicine. May interact with anticoagulants and hypoglycemic agents. No established RDA/UL.