Mushrooms and the Kidneys, Oxalates and the Liver

Warning signs first. Jaundice, meaning yellow skin and yellow whites of the eyes, can have several causes and needs a clinician. [1] A reishi powder case report began with headache and abdominal pain. [2] If you have any of these after starting a mushroom product, stop and call a clinician promptly; for an emergency call 911. In the chaga case reports below, kidney function fell and some people needed dialysis, so tell your care team about the product if your kidney tests change. [3]

Do mushrooms have oxalates?

Oxalate is a natural substance that can form crystals in the kidneys. A 2002 study measured raw, commercially grown mushrooms and found total oxalate of 58.9 to 104.1 mg per 100 g of dry matter. [4] The authors called the levels low compared with other common oxalate-containing vegetables. [4] NIDDK's kidney stone page lists nuts, peanuts, rhubarb, spinach and wheat bran for people with calcium oxalate stones; the page we read did not name mushrooms. [5]

Proper evidence not found that ordinary culinary mushrooms cause kidney stones. We searched PubMed (oxalate content of mushrooms, chaga oxalate) and the NIDDK stone page. If you form stones, ask your clinician or dietitian about oxalate in your own diet. [5]

Chaga and the kidneys

Chaga (Inonotus obliquus) is different from culinary mushrooms. Case reports link chaga powder to oxalate nephropathy, kidney injury from oxalate crystals.

The Japanese authors wrote that chaga contains extremely high oxalate concentrations. [3] The 2020 authors called it a potential risk factor for chronic kidney disease. [6] Case reports cannot show how common this is. People with kidney disease should ask their kidney team before any chaga product; see chaga side effects, oxalates and kidney concerns.

Other kidney points

• The National Kidney Foundation says herbal supplements can make kidney disease worse or interact with prescription medicines, and that some contain ingredients or contaminants that can damage the kidneys. [8] It did not name mushrooms on the page we read.
• MSK lists "help your kidneys work better" among reasons people use cordyceps, but that is a traditional or marketed use. [9] Do not treat it as a reason to self-treat kidney disease.
• A 2025 meta-analysis of reishi trials found no significant change in liver enzymes; the evidence was very low quality. [10]

Reishi and the liver

MSK lists liver injury among reishi side effects. [11] Two patients (one reported from Hong Kong, one in Thailand) developed liver problems after switching from boiled lingzhi to powder; the Thai authors' own case was fatal. [12] A 2023 report described acute hepatitis after reishi powder and alcohol; the patient's labs and symptoms resolved after about two weeks. [2] See reishi side effects and liver reports and liver safety and supplements.

Agaricus blazei products

Japanese physicians described two cancer patients with severe liver injury after extracts of Agaricus blazei Murill, one combined with a Ganoderma lucidum extract and one with fucoidan. They did not tell their physicians about the products. [13] The authors suggested the mushroom's immune-stimulating action caused injury resembling autoimmune hepatitis. [13] GBIF lists Agaricus blazei Murrill and Agaricus subrufescens Peck as separate accepted names, so check which species a product states. [14] See Agaricus subrufescens.

Other mushrooms

The MSK pages we read for chaga, maitake, cordyceps, shiitake and turkey tail did not list liver injury among side effects. [15] [16] [9] [17] [18] That is not proof of safety.

Poisoning from wild mushrooms

Wild mushroom poisoning can damage the heart, liver and kidneys. [19] It is a separate emergency: call Poison Help at 1-800-222-1222. See mushroom poisoning: warning signs and urgent help.