Story at-a-glance

• Evidence shows chaga can support your immune system and reduce inflammation; it's effective against HIV-1, influenza virus H3N2 and herpes simplex virus 2
• Compounds found in chaga were effective against cancer cells in the lab, reducing primary tumors by 60% and metastatic growth by 25%
• In animal studies, the polysaccharides had a therapeutic effect on blood glucose; they also lowered proinflammatory cytokines and aided in the recovery of insulin-producing pancreatic beta cells
• Indigenous people in and around Russia use chaga to aid in digestion, respiration and detoxification
• Limitations are in place as to the use of the product, as the most potent variety is wild harvested in remote areas of Siberia, which makes it impractical to grow for commercial purposes

Chaga goes by several names. The botanical name for the fungus is Inonotus obliquus. The Chinese call it Hua Jie Kong Jun or Bai Hua Rong.1 While it is often referred to as a mushroom, it grows as a dense black colored mass on the outside of trees. Most commonly it infects birch trees.

Chaga does not form a fruiting body the way most mushrooms do, but rather a mass of mycelia that incorporates decaying bits of the birch tree it grows on. Mycelia are microscopic vegetative fungi parts that combine to create a whole growing organism.2

As they grow out from the center they consume the nutrients, leaving an open ring. As the growth spreads, it consumes what's around it. This classifies most fungi as parasites and decomposers.

The inside of the chaga is a rusty, yellow brown color that may be mottled or have cream-colored veins.3 A chaga infection doesn't usually show up on a tree until it's reached 40 years or more. The tree can usually withstand the infection for about 20 years before it ultimately dies.

Those who harvest chaga chop it from the tree and then allow it to regrow for three to 10 years before it is harvested again. However, harvesting does not stop the infection.

When compared to other medicinal fungi, research has shown chaga has strong antioxidant activity. However, it was the infrequently found fruiting body in one study that exhibited the highest potential.4

History of Medicinal Chaga

Until the 1990s, just a few countries in Southeast Asia and Russia5 were using chaga as folk medicine.6 One of the first recorded clinical trials was done in the 1950s at the Moscow Medical Institute.7 Studies have continued with scientists evaluating chaga's uses in immune regulation, digestion, nervous system functioning, cardiovascular activities and respiratory system support.

There is also research into its potential to help slow the growth of tumors in patients with cancer. While the early history of chaga is not well documented, we do know indigenous people in Russia used it to help their digestion. They wrote that it made them feel full and helped with internal cleaning, a process Westerners call detoxification.

The anti-inflammatory properties likely made chaga useful as a soap when combined with lard and ash to help soothe skin sores.8 Chaga was often prepared as a tea (and still is) and taken until the individual felt better.

Another group of people living on the Kuril Islands just off the northeast coast of Russia used it for stomach pain and inflammation.9 Some also smoked pipes filled with powdered chaga during religious ceremonies. There are no known medicinal effects from smoking the powder, but it is clear that inhaling burning material, such as tobacco, can damage your lungs.

Chaga Demonstrates Antiviral Properties

Many of the health benefits may be the result of immune support and anti-inflammatory properties, as shown in several studies. The polysaccharides found in fungal growths are the primary component used to support the immune system.10

In a review of the literature, researchers found extractions or aqueous solutions of chaga at different concentrations11 demonstrated effectiveness against herpes simplex virus 2, influenza virus H3N2 and HIV-1. They also found it has antiretroviral activity and wrote:12

"Aqueous extracts and melanin derived from natural chaga Inonotus obliquus exhibit activity against many viruses: human immunodeficiency type 1, herpes simplex virus type 2, West Nile, influenza, vaccinia and monkeypox viruses [31, 34]. This broad spectrum of antiviral activity is associated with complex composition of compounds."

In one lab study13 using the BELYU1102 strain of Inonotus obliquus, researchers found the active polysaccharides from chaga improved production of IgM antibodies, but didn't have an effect on the expression of several other types of immune cells, including T cells.

Extracts from chaga fungus demonstrate anti-inflammatory properties in the lab14 and in animal studies15 as well as pain reduction response in vitro and in vivo in an animal study.16 In mice, oral administration specifically reduced the inflammatory effects of colitis.17

Does Chaga Affect Cancer Growth?

Two compounds unique to the chaga fungus are betulin and betulinic acid.18 The fungus gets these from the birch trees on which it grows. The leaders of one study19 evaluated the effectiveness of these two compounds, plus inotodiol, which is also found in chaga in the treatment of cancer cells in the lab.

The researchers used growths from a stand of trees discovered in Normandy, France. They compared those to concentrations found in chaga harvested in Ukraine and in Canada under colder conditions. The goal was to explore potential cytotoxicity against cancer-derived cells and compare the concentration of metabolites using chaga from three locations.

Human lung adenocarcinoma cells and human bronchial epithelial cells were used, with researchers finding that the French stand of trees had more betulin and betulinic acid than the other two. However, the Canadian trees had higher levels of inotodiol. In an animal study using the whole chaga fungus, researchers demonstrated daily intake reduced primary tumors by 60% and metastatic growth by 25%.20

The fungus appears to have in vitro and in vivo effects against tumor cells in animals. While investigating the mechanism of action, some scientists have found the compounds do not appear to have a direct effect against tumor cells, but rather an indirect effect by stimulating the immune system.21,22

Another animal model23 was used to examine different components against colon cancer cells; researchers found ergosterol peroxide was the most effective of all chaga's components in inhibiting growth. They found the compound also suppressed proliferation and inhibited colitis-like symptoms by down-regulating a signaling pathway that increased cancer cell death.

Results from lab studies24 demonstrate an ethanol extract of the chaga mushroom could inhibit human colon cancer cell proliferation. Chaga also contributes to improved quality of life during and after chemotherapy and radiation treatments by reducing side effects from a compromised immune system.25

Researchers have also found that the antioxidants in the fungus can prevent the development of cancer cells26 and that they may be active against human prostate and breast cancer cells.27

Polysaccharides in Chaga May Help Control Blood Glucose

In 2018, 26.8 million people in the U.S. had a diagnosis of diabetes. The American Diabetes Association28 estimates there were another 7.3 million who were undiagnosed. It is the seventh leading cause of death and a contributing factor in others.29

To impact this devastating condition, researchers continue to seek out nutritional supplements to help stabilize blood glucose, as uncontrolled blood glucose is a symptom of diabetes but not the cause. The polysaccharides found in the fungal growth of chaga had a therapeutic effect on blood glucose levels in a study involving animals.30

After diabetes was induced in rats, they were fed chaga polysaccharides. The intervention restored abnormal indices, including blood glucose and it alleviated oxidative stress. Additionally, the treatment lowered proinflammatory cytokines and aided in the partial recovery of pancreatic beta-cells responsible for producing insulin.

The authors of a literature review found similar results.31 In another animal study, researchers found the water-soluble and water-insoluble polysaccharides had a hypoglycemic effect, most notably from "β-glucan, heteroglucan, and their protein complexes."32

Future Use of Chaga Has Limitations

Chaga produced in Russia is under strict directions for the valuation of the individual harvest and production of derivatives, which are different from the rest of the world.33 Russian law limits the extraction to a hot water process that reduces or eliminates the bioavailability of terpenes, such as betulinic acid.

The research data on chaga outside of Russia demonstrate these components have powerful health benefits. Like most medicinal plants, the health potential in the fungus is also related to the conditions under which it is grown.

The highest quality chaga comes from harsh climates with larger swings in temperature, such as Siberia, Finland, North Korea and parts of the North American continent. Russia has a long history of commercially harvesting chaga, which had mostly stayed within the country until recently. Wild-harvested chaga is in greater demand but needs years to fully develop.

However, while the source of wild-harvested chaga is immense, one researcher concluded it may not be economically feasible to travel deep into the Siberian forest to harvest it commercially.

Wild grown chaga in natural environmental conditions have the highest levels of medicinal bioactive compounds, but some benefit has been derived from the melanins extracted from cultured biomass.34

Chaga is most commonly used by Westerners as tea. Brewing the tea correctly yields an earthy, natural tasting tea with hints of vanilla. Fresh chaga is susceptible to mold, so storing it correctly is vital. Discover how to properly brew and store chaga tea in "Chaga Tea: Benefits of This Unusual but Health-Boosting Beverage."