Background

• Inonotus obliquus, a mushroom commonly known as "chaga," is widely used in folk medicine in Siberia, North America, and northern Europe. Chaga is a member of the Basidiomycetes (true mushrooms) family and widely distributed in Europe, Russia, and the northern regions of Japan. When growing on the tree, chaga produces a black, long-lasting woody growth called a "conk," which absorbs nutrients and important chemicals from the wood. When the chaga conk flower ripens, it falls to the forest floor. It is estimated that only about 0.025% of trees will grow a chaga conk, making the chaga mushroom somewhat rare.
• Chaga mushrooms have been used in folk medicine since the 16th Century as a remedy for cancer, stomach problems, ulcers, and tuberculosis of the bones. Chaga has been collected and consumed for centuries in Asia. Although medicinal use of chaga and other mushrooms is rare in Western countries, reports have described its nutritional value and the value of the biologically active starches and other plant compounds (flavonoids and lipids) that it contains.
• Some reports describe chaga as having the following effects: antibacterial; antiviral; toxic; immune system-regulating; anticancer; cardiovascular; pain-relieving; blood sugar-lowering; and plant, insect, or worm-killing activities. However, there is currently a lack of evidence to support using chaga to treat any medical condition.

References

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