Mushrooms

Chaga

Also called: inonotus obliquus

A fungus that grows on birch trees.

Why people take it
Immunity, antioxidants.
What the evidence says
No good human studies.
How it is usually taken
As tea or 500 mg to 1.5 g of extract a day for short periods.
Be careful
Very high in oxalate; has caused kidney damage. May add to blood thinners and diabetes medicines.
Medicines it can interact with
High in oxalate (kidney damage reports); may add to blood thinners and diabetes medicines.

Other mushrooms

Lion's maneTurkey tailShiitake extractMaitakeTremellaAgaricus blazeiMushroom coffeeLingzhi spores

Common questions

What is Chaga?

A fungus that grows on birch trees.

Why do people take Chaga?

Immunity, antioxidants.

Does Chaga work?

No good human studies.

How much Chaga do people take?

As tea or 500 mg to 1.5 g of extract a day for short periods.

Is Chaga safe?

Very high in oxalate; has caused kidney damage. May add to blood thinners and diabetes medicines.

Does Chaga interact with medicines?

High in oxalate (kidney damage reports); may add to blood thinners and diabetes medicines.

Sources and further reading

Last reviewed 31 October 2026. Written by Satya Babu.

🔎 Search all supplements

For information only, not medical advice. Supplements are not medicines: they are not tested and approved like drugs before they are sold, and they can interact with medicines. Talk to your doctor or pharmacist before you start one, especially if you are pregnant or breastfeeding, take regular medicines, or have kidney, liver or heart disease.