Ganoderma (Reishi Tcm) for Immune Function

Research suggests that Ganoderma lucidum (Reishi) may support certain aspects of immune function, though the evidence base is limited and results are mixed. A mouse model study found that Ganoderma lucidum extract slowed tumor growth and appeared to modulate immune signaling pathways, including effects on cytokine levels, without apparent organ toxicity — though animal studies do not reliably predict human outcomes. A 24-week human trial examining Ganoderma in combination with another herbal formula in rheumatoid arthritis patients found largely no significant differences in immune markers compared to placebo, with the exception of a modest reduction in the inflammatory signaling molecule IL-18 under laboratory stimulation conditions. Taken together, the available studies — one preclinical animal study and one small human combination-formula trial — offer only preliminary and inconsistent signals, making it difficult to draw firm conclusions about Ganoderma's effects on human immune function at this time.