Chaga (Inonotus obliquus)

Chaga is sold as a «natural antioxidant» and longevity supplement on the high polyphenol and melanin content, promising oxidative stress protection and aging slowdown. Cochrane 2012 on antioxidant supplements recorded no all-cause mortality reduction in healthy people; for some components (beta-carotene) – increased mortality. No quality human RCTs with aging biomarker, telomere or all-cause/cardiovascular mortality endpoints. If chaga was recommended for «life extension» or «anti-age», consider seeking a second opinion. Important: chaga oxalates raise nephrolithiasis and oxalate nephropathy risk with prolonged intake.

Chaga is the top-selling «anti-tumour» mushroom in Russia and the West, promising prevention and treatment of malignancies. In Russia Befungin is registered as OTC «for gastritis and peptic ulcer, as symptomatic therapy in cancer» without confirmed antitumour efficacy. No quality international RCTs with tumour response or overall survival endpoints. MSKCC monograph 2023 classifies the evidence base as insufficient. Main risk – oxalate nephropathy: acute renal failure cases with high-dose chaga reported. If chaga was recommended for cancer as substitute for standard therapy (surgery, chemotherapy, radiotherapy, immunotherapy), consider seeking a second opinion from an oncologist.

Chaga is sold for «immunity boosting» and «cold prevention». No Cochrane systematic review on chaga for colds or respiratory viral infections. No quality international RCTs with frequency and symptom duration endpoints. AAFP and SEIMC for the common cold recommend symptomatic therapy; chaga is not in international guidelines.