Canadian researchers have assessed available research on the health benefits and composition of the Chaga mushroom, Inonotus obliquus. With a long history of traditional use for medicinal purposes and resulting research on pharmaceutical benefits, the review suggests additional potential of the mushroom in nutrition for its antioxidant, anti-inflammatory, antiviral and antitumor potential.
The research team laments that the product’s benefits are “virtually untapped” due to a limited understanding of its mycochemical composition and bioactives. The authors note that Chaga is a promising natural resource with many potential applications.
Chaga mushrooms contain an 8.57% concentration of beta-glucans — bioactive compounds with immune-supporting benefits — as well as antioxidants, vitamins and minerals.
“Chaga’s beta-glucans hold potential as a natural food component and supplement with numerous untapped medical potentials. So far, Chaga and its crude extracts have been completely harmless. However, the safety and toxicology of the fungus has not been extensively investigated,” the study’s lead author, Eric Fordjour, from the University of Western Ontario, Canada, tells Nutrition Insight.
“Emphasizing the significance of a balanced diet that focuses on the bioactivity of nutrients, then individual foods, the review advises that Chaga supplementation presents an exciting opportunity for those seeking a holistic approach to overall well-being.”
Fordjour highlights that Chaga beta-glucans are a source of nutrients that can profoundly impact well-being. Moreover, Chaga contains high levels of antioxidants, proteins, minerals — such as potassium, manganese and zinc — fiber and vitamins, such as vitamin B complex and vitamin D.
The antioxidant activities of Chaga also stem from its concentration of polyphenols and flavonoids. Although the composition of Chaga extracts varies, the review highlights the compound hispidin and its analogs found in extracts, which have antioxidant and anti-inflammatory properties.
The review, published in Frontiers in Pharmacology, also highlights that multiple studies demonstrate Chaga’s ability to counteract the effect of free radicals and related health benefits. For example, one research found that Chaga improved learning and memory in mice with amnesia by increasing endogenous antioxidants.
Other research linked the antioxidant properties of Chaga to heart health, diabetes and cancer management. For example, one study indicates that mushroom extracts may lower blood sugar levels.
Immunity and anti-cancer potential
According to the review, beta-glucans have been linked to health-promoting properties, such as immune modulation and anti-inflammatory and antioxidant effects. These dietary fibers can be found in yeast, mushrooms, bacteria and algae.
“Our immune system acts as our body’s defense mechanism, and Chaga beta-glucans have showcased their exceptional ability to modulate and enhance immune function through mechanisms like activating macrophages,” explains Fordjour.
A study on the methanol and ethanol extracts of Chaga suggests they inhibit macrophage activity by reducing the production of inflammatory mediators. Another research linked extracts to reduced edema and mucosal damage.
The compounds betulin and betulinic acid found in Chaga are also reported to modulate the activities of immune cells and prevent pro-inflammatory production, illustrates the review. Moreover, studies have reported the inhibitory properties of bioactive compounds in Chaga mushrooms against several viruses, such as hepatitis C, HIV and herpes simplex virus.
Seizing the fungus’ health potential, Canadian company Oceanix Biotechnology launched ChagaPure last year, a range of Chaga mushroom extract powders with potent antioxidant abilities to enhance immunity. In clinical trials, the ingredients showed antibacterial, antiviral and antifungal properties.
Beyond immunity support, the review authors identified the potential of beta-glucans in treating cancer, highlighting that the compounds may complement existing cancer therapies.
They found that extracts reduced the activity of macrophage cells and induced cytotoxicity in vitro in human prostate cancer and breast cancer cells. Hot water extracts were linked to anti-cancer activity in human colon cancer cells.
Need for further research
Although Chaga and its extracts have been consumed extensively, the review has found limited studies on the safety and toxicology of the fungus. Therefore, the authors warn consumers before incorporating the product into their diet.
At the same time, the few studies that examined mushroom consumption found that it is generally safe for consumption. However, oxalic acid — a toxic substance in the mushroom — must be further investigated for potential human risk.
One study suggested limiting the concentration of Chaga in ethanol extracts to 100 g/mL as higher concentrations were harmful to skin cells. Other research found no impact of Chaga on weight fluctuations or effects on liver and kidney functions.
The review concludes: “Most claims about Chaga’s traditional medicinal properties have also been proven true, either by in vitro or in vivo testing.” It suggests that clinical trials and translational studies are crucial to obtain more information on the fungus as a basis for future research and to understand better the mechanisms underlying the health-promoting activities of Chaga beta-glucans.
According to the authors, future research could focus on determining effective dosages for Chaga beta-glucans, investigating interactions with other medications and unraveling the specific mechanisms responsible for their anti-cancer and immunomodulating effects.
By Jolanda van Hal