Reishi Mushroom for Immune Function

Research suggests that Reishi mushroom may offer modest immune-supporting benefits, particularly in the context of cancer care, based on two Cochrane systematic reviews — both drawing on the same pool of five randomized controlled trials — that found patients taking Reishi alongside conventional chemotherapy or radiotherapy showed improvements in immune cell markers, specifically CD3, CD4, and CD8 T-lymphocyte percentages, as well as modest gains in quality of life compared to conventional treatment alone. Studies indicate these findings are promising but should be interpreted cautiously, as both reviews consistently flagged the poor methodological quality of the underlying trials, the absence of long-term survival data, and the limited number of studies available. The overall direction of the evidence is mixed — supportive enough to suggest potential adjunctive value, but not sufficiently robust to draw firm conclusions about Reishi's independent effect on immune function. Reishi was generally reported as well tolerated with minor side effects, though readers should be aware that the current evidence base remains preliminary and further high-quality research is needed.