Introduction
Chaga mushroom (Inonotus obliquus), a medicinal fungus traditionally used in Northern Europe, Russia, and other parts of Asia, has gained significant attention in recent years for its potential health benefits (Duru et al., 2023). This dark, charcoal-like mushroom grows primarily on birch trees in cold climates and has been used for centuries in folk medicine to promote overall health and well-being.
Recent scientific research has begun to uncover the mechanisms behind chaga’s purported benefits, which include boosting the immune system, fighting inflammation, and even exhibiting anticancer properties (Szychowski et al., 2021; Gery et al., 2018; Zhao & Zheng, 2021). In this article, we will explore the nutritional profile of chaga mushrooms and delve into the evidence supporting their potential health benefits, as well as discuss safety considerations and precautions for those interested in incorporating this fascinating fungus into their health regimen.
Nutritional Profile
Chaga mushrooms are low in calories, high in fibre, and packed with antioxidants (Duru et al., 2023). They contain a wide array of beneficial compounds, including polysaccharides, triterpenoids, polyphenols, and melanin, which contribute to their potential health benefits (Duru et al., 2023).
Polysaccharides, particularly beta-glucans, are the primary active compounds found in chaga mushrooms. These complex carbohydrates have been shown to possess immunomodulatory, anti-inflammatory, and anticancer properties (Szychowski et al., 2021). Triterpenoids, such as betulinic acid and inotodiol, are another class of compounds found in chaga that have demonstrated potential anticancer and anti-inflammatory effects (Zhao & Zheng, 2021).
Chaga mushrooms are also rich in polyphenols, which are potent antioxidants that help protect cells from damage caused by free radicals and oxidative stress (Gery et al., 2018). Melanin, a pigment responsible for chaga’s dark colour, has been found to possess antioxidant and immunomodulatory properties as well (Duru et al., 2023).
Potential Health Benefits
Immune System Support
One of the most well-known benefits of chaga mushrooms is their ability to support and enhance immune function. The beta-glucans and other polysaccharides found in chaga have been shown to stimulate the immune system by increasing the production of immune cells and cytokines (Szychowski et al., 2021).
In vitro and animal studies have demonstrated that chaga extracts can enhance the body’s defense against infections and reduce inflammation (Szychowski et al., 2021). For example, a study by Arata et al. (2016) found that oral administration of chaga aqueous extract to mice significantly increased the production of natural killer cells and cytokines, leading to enhanced immune function and suppression of tumour growth.
These immunomodulatory effects may also contribute to chaga’s potential in preventing and treating various chronic diseases, such as cancer and inflammatory disorders (Duru et al., 2023).
Antioxidant Properties
Chaga mushrooms are a potent source of antioxidants, which help protect cells from damage caused by free radicals and oxidative stress (Gery et al., 2018). The high content of polyphenols and melanin in chaga contributes to its strong antioxidant capacity (Duru et al., 2023).
In a study by Gery et al. (2018), chaga extracts demonstrated significant antioxidant activity and protected human lung cells from oxidative damage induced by hydrogen peroxide. The authors suggested that the antioxidant properties of chaga may contribute to its potential anticancer and anti-inflammatory effects.
Oxidative stress has been linked to various chronic diseases, including cancer, cardiovascular disease, and neurodegenerative disorders (Gery et al., 2018). By reducing oxidative stress and protecting cells from damage, the antioxidants found in chaga mushrooms may play a role in preventing and managing these conditions.
Anticancer Potential
Several in vitro and animal studies have investigated the anticancer potential of chaga mushrooms, with promising results. These studies have shown that chaga extracts can inhibit the growth and spread of various types of cancer cells, including lung, breast, colon, and liver cancer (Arata et al., 2016; Baek et al., 2018; Zhao & Zheng, 2021).
For instance, a study by Baek et al. (2018) found that chaga extracts induced apoptosis (programmed cell death) in human lung adenocarcinoma cells, while having minimal effects on normal lung cells. The authors attributed the anticancer effects to the presence of specific triterpenoids and polyphenols in chaga.
Similarly, Arata et al. (2016) demonstrated that oral administration of chaga aqueous extract to mice bearing lung cancer cells significantly suppressed tumour growth and prolonged survival compared to the control group. The anticancer effects were associated with increased immune cell activity and enhanced production of cytokines.
The anticancer potential of chaga mushrooms is thought to be mediated through various mechanisms, including antioxidant and immunomodulatory effects, induction of apoptosis, and inhibition of angiogenesis (the formation of new blood vessels that support tumour growth) (Zhao & Zheng, 2021). However, it is important to note that most of these findings are based on in vitro and animal studies, and more human clinical trials are needed to confirm the efficacy and safety of chaga mushrooms in cancer prevention and treatment.
Blood Sugar Regulation
Chaga mushrooms have shown potential in regulating blood sugar levels and improving insulin sensitivity, which may be beneficial for individuals with diabetes or at risk of developing the condition. Animal studies have provided insight into the hypoglycaemic effects of chaga polysaccharides and the possible mechanisms involved.
Wang et al. (2017) investigated the anti-diabetic effects of Inonotus obliquus polysaccharides (IOPs) in streptozotocin-induced type 2 diabetic mice. The study found that IOPs significantly reduced fasting blood glucose levels, improved glucose tolerance, and increased insulin sensitivity compared to the control group. The authors suggested that the hypoglycaemic effects of IOPs may be mediated through the regulation of glucose metabolism and insulin signalling pathways, specifically the PI3K-Akt pathway.
Furthermore, the study by Wang et al. (2017) also demonstrated that IOPs treatment led to a significant reduction in serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol (LDL-C) levels, while increasing high-density lipoprotein cholesterol (HDL-C) levels in diabetic mice. These findings suggest that chaga polysaccharides may have additional benefits for cardiovascular health in individuals with diabetes.
While these animal studies provide promising evidence for the potential of chaga mushrooms in blood sugar regulation, more human clinical trials are needed to confirm these effects and determine the optimal dosage and long-term safety of chaga supplementation for diabetes management.
Cholesterol Reduction
In addition to their potential hypoglycaemic effects, chaga mushrooms have also been investigated for their ability to reduce cholesterol levels, which may contribute to improved cardiovascular health. Animal studies have provided some evidence for the cholesterol-lowering properties of chaga extracts and the possible mechanisms involved.
As mentioned earlier, the study by Wang et al. (2017) found that Inonotus obliquus polysaccharides (IOPs) significantly reduced serum total cholesterol, triglycerides, and LDL-C levels, while increasing HDL-C levels in streptozotocin-induced type 2 diabetic mice. The authors suggested that the cholesterol-lowering effects of IOPs may be attributed to their antioxidant and anti-inflammatory properties, which could help protect against oxidative stress and inflammation-induced damage to the cardiovascular system.
Another study by Choi et al. (2010) investigated the effects of chaga mushroom extracts on lipid metabolism in rats fed a high-fat diet. The study found that supplementation with chaga extracts significantly reduced total cholesterol, LDL-C, and triglyceride levels, while increasing HDL-C levels compared to the control group. The authors proposed that the cholesterol-lowering effects of chaga may be due to its ability to inhibit the absorption of dietary cholesterol and promote the excretion of bile acids.
These animal studies suggest that chaga mushrooms may have potential in reducing cholesterol levels and improving cardiovascular health. However, human clinical trials are necessary to confirm these effects and determine the optimal dosage and long-term safety of chaga supplementation for cholesterol management. Additionally, it is important to note that while chaga may have cholesterol-lowering properties, it should not be used as a substitute for prescribed cholesterol medications without consulting a healthcare professional.
Safety and Precautions
While chaga mushrooms are generally considered safe for consumption, there is limited research on their long-term safety and appropriate dosage in humans (Memorial Sloan Kettering Cancer Center, n.d.). It is essential to exercise caution when using chaga supplements and to consult with a healthcare provider before incorporating them into your health regimen.
One potential concern is the interaction between chaga and certain medications, particularly blood thinners and diabetes medications (Memorial Sloan Kettering Cancer Center, n.d.). Chaga contains compounds that may enhance the effects of these medications, leading to an increased risk of bleeding or hypoglycaemia. Therefore, individuals taking blood thinners or diabetes medications should consult their healthcare provider before using chaga supplements.
Chaga mushrooms should also be used with caution in individuals with autoimmune diseases, as the immunomodulatory effects of chaga may potentially exacerbate these conditions (Memorial Sloan Kettering Cancer Center, n.d.). Similarly, those with bleeding disorders should exercise caution when using chaga, as it may increase the risk of bleeding.
It is important to note that the safety of chaga mushrooms during pregnancy and lactation has not been well-established (Memorial Sloan Kettering Cancer Center, n.d.). Therefore, pregnant and breastfeeding women should avoid using chaga supplements until more research is available.
When purchasing chaga supplements, it is crucial to choose products from reputable sources to ensure quality and purity. Some chaga supplements may be contaminated with heavy metals or other harmful substances, so it is essential to select products that have been tested for purity and potency by a third-party organisation.
In summary, while chaga mushrooms have shown promise in various health applications, more human clinical trials are needed to establish their efficacy and safety. As with any dietary supplement, it is essential to consult with a healthcare professional before incorporating chaga into your health regimen, especially if you have pre-existing medical conditions or are taking medications.
Conclusion
In conclusion, chaga mushrooms have emerged as a promising functional food with a wide range of potential health benefits. The research discussed in this article highlights the immunomodulatory, antioxidant, anticancer, hypoglycaemic, and cholesterol-lowering properties of this medicinal fungus. The unique combination of polysaccharides, triterpenoids, polyphenols, and melanin found in chaga contributes to its potent bioactive effects.
While the findings from in vitro and animal studies are encouraging, it is essential to acknowledge that more human clinical trials are needed to fully understand the efficacy and safety of chaga mushrooms in various health applications. As with any dietary supplement, it is crucial to consult with a healthcare professional before incorporating chaga into your health regimen, especially if you have pre-existing medical conditions or are taking medications.
As interest in natural and functional foods continues to grow, chaga mushrooms may play an increasingly important role in promoting overall health and well-being. However, it is essential to approach their use with caution and to make informed decisions based on the available scientific evidence. By prioritising safety and efficacy, we can harness the potential of this fascinating medicinal fungus while minimising the risks associated with its use.
Key Highlights of Learnings and Actionable Tips
- Inonotus obliquus (Chaga mushroom) polysaccharides (IOPS) have shown promising anticancer, antioxidant, antivirus, hypoglycemic and hypolipidemic activities in various studies
- IOPS can be extracted using modern methods like ultrasonic-microwave assisted extraction to improve yield and purity compared to traditional hot water extraction
- The triple helix conformation of IOPS may contribute to its excellent biological activities
- IOPS has demonstrated ability to inhibit proliferation and induce apoptosis in various cancer cell lines in vitro and in animal models
- Potential mechanisms of IOPS anticancer effects include regulating signaling pathways, metalloproteinase expression, and stimulating immune response
- IOPS shows hypoglycemic and hypolipidemic effects in diabetic animal models, possibly by regulating enzyme activity, glucose metabolism, and insulin sensitivity
- The antioxidant activity of IOPS is related to its ability to scavenge free radicals and regulate antioxidant enzymes
- IOPS has exhibited antiviral effects against viruses like HIV, HSV, and feline calicivirus in cell models
- While IOPS appears to have low toxicity, more research is needed to fully evaluate its safety especially for long-term use
- Chaga mushroom is already used in some functional foods and supplements, but clinical research is still limited
What is the typical dosage of Chaga mushroom extract used in studies?
In animal studies, Chaga mushroom polysaccharide doses typically range from 50-900 mg/kg body weight per day. For example, one study used 50-100 mg/kg daily doses in mice to evaluate antitumor effects. However, optimal dosage for humans has not been well established since there is a lack of clinical trials. Existing Chaga mushroom supplements often recommend 1-3 grams of extract per day, but this is not necessarily backed by scientific evidence. Consulting with a healthcare professional is advised before taking Chaga supplements.
Are there any known interactions between Chaga mushroom and medications?
Chaga mushroom may have blood-thinning effects due to its antioxidant content. Therefore, it could potentially interact with anticoagulant and antiplatelet medications, increasing the risk of bleeding. Chaga may also lower blood sugar, so taking it along with diabetes medications could cause hypoglycemia. However, these potential interactions have not been well studied in humans. It’s important to discuss with your doctor before combining Chaga with any medications to avoid adverse interactions.
Can Chaga mushroom be consumed as a food or beverage?
Yes, Chaga mushroom is consumed as a functional food or beverage in some parts of the world, especially Russia and other northern European countries. It is traditionally brewed into a tea or coffee-like beverage. Chaga powder can also be added to smoothies, soups, or other recipes. However, Chaga is quite bitter so it is often mixed with other ingredients like honey or coffee to improve flavor. The safety of long-term consumption of Chaga food products is not known.
What part of the Chaga mushroom contains the beneficial polysaccharides?
The beneficial polysaccharides are primarily found in the dark outer surface of the Chaga mushroom, which is called the sclerotium. The sclerotium develops on the outside of birch trees infected with the fungus and has a dark, charcoal-like appearance. The interior has a softer, orange-brown color. Both the sclerotium and the inner mycelium contain polysaccharides, but the sclerotium is most commonly used for medicinal properties.
Has Chaga mushroom been tested in any human clinical trials?
To date, there have been very few clinical trials evaluating Chaga mushroom in humans. Most of the research has been limited to cell culture and animal models. A few small human studies have looked at the effects of Chaga on diabetes, oxidative stress, and inflammatory markers, with some promising results. However, large-scale, well-designed clinical trials are still lacking. More human research is needed to determine the efficacy and safety of Chaga mushroom for various health conditions. The existing evidence is not strong enough to recommend Chaga for the treatment or prevention of any diseases.
References
Arata, S., Watanabe, J., Maeda, M., Yamamoto, M., Matsuhashi, H., Mochizuki, M., Kagami, N., Honda, K., & Inagaki, M. (2016). Continuous intake of the Chaga mushroom (Inonotus obliquus) aqueous extract suppresses cancer progression and maintains body temperature in mice. Heliyon, 2(5), e00111. https://doi.org/10.1016/j.heliyon.2016.e00111
Baek, J., Roh, H. S., Baek, K. H., Lee, S., Lee, S., Song, S. S., & Kim, K. H. (2018). Bioactivity-based analysis and chemical characterization of cytotoxic constituents from Chaga mushroom (Inonotus obliquus) that induce apoptosis in human lung adenocarcinoma cells. Journal of Ethnopharmacology, 224, 63-75. https://doi.org/10.1016/j.jep.2018.05.025
Duru, K. C., Kovaleva, E. G., Danilova, I. G., & Bijl, P. (2023). The pharmacological potential and possible molecular mechanisms of action of Inonotus obliquus from preclinical studies. Phytotherapy Research, 37(4), 1559-1584. https://doi.org/10.1002/ptr.7724
Gery, A., Dubreule, C., André, V., Rioult, J. P., Bouchart, V., Heutte, N., Eldin de Pecoulas, P., Krivomaz, T., & Garon, D. (2018). Chaga (Inonotus obliquus), a future potential medicinal fungus in oncology? A chemical study and a comparison of the cytotoxicity against human lung adenocarcinoma cells (A549) and human bronchial epithelial cells (BEAS-2B). Integrative Cancer Therapies, 17(3), 832-843. https://doi.org/10.1177/1534735418757912
Szychowski, K. A., Skóra, B., Pomianek, T., & Gmiński, J. (2021). Inonotus obliquus – from folk medicine to clinical use. Journal of Traditional and Complementary Medicine, 11(4), 293-302. https://doi.org/10.1016/j.jtcme.2020.08.003
Wang, J., Wang, C., Li, S., Li, W., Yuan, G., Pan, Y., & Chen, H. (2017). Anti-diabetic effects of Inonotus obliquus polysaccharides in streptozotocin-induced type 2 diabetic mice and potential mechanism via PI3K-Akt signal pathway. Biomedicine & Pharmacotherapy, 95, 1669-1677. https://doi.org/10.1016/j.biopha.2017.09.104
Zhao, Y., & Zheng, W. (2021). Deciphering the antitumoral potential of the bioactive metabolites from medicinal mushroom Inonotus obliquus. Journal of Ethnopharmacology, 265, 113321. https://doi.org/10.1016/j.jep.2020.113321
