Commonly referred to as the “mushroom of immortality”, reishi is a powerful medicinal mushroom that’s been used for thousands of years in Chinese Medicine for its variety of health promoting properties, including its ability to reduce stress and support the immune system. Native to China and Japan, reishi is an orange-red “woody” fungus with a shiny exterior that traditionally grows on the wood of hardwood trees.

In Herbal Medicine reishi is considered an adaptogen, meaning it helps the body adapt to stress, whether emotional, physical or environmental. Additionally, reishi is a powerful immune system modulator (which means it reduces its activity when over stimulated, and boosts it when it’s weak), which is likely why it has historically been associated with longevity and immortality. Also referred to as “the king of mushrooms”, reishi was not traditionally widely available until it was commercially cultivated, and was in fact reserved for royalty and nobility.

Perhaps the most widely used mushroom in Chinese Medicine, reishi boasts countless health benefits, for which research is ongoing. In addition to stress and immunity, other studied health benefits include its potential positive effects on cancer, blood sugar control, liver function and allergies, to name a few.

Active constituents
Polysaccharides, oligosaccharides, triterpenoids, peptides and proteins, mineral elements (zinc, copper, iodine, selenium, and iron), vitamins, and amino acids.

Cautions and warnings 
If you are pregnant or breastfeeding, consult a health care practitioner prior to use. 

Known Adverse Reactions
Hypersensitivity/allergy can occur; in which case, discontinue use.

AVAILABLE RESEARCH

Stress and stress-related fatigue

In this study of 132 patients suffering from neurasthenia (a medical condition characterized by lassitude, fatigue, headache, and irritability, associated chiefly with emotional disturbance), it was concluded that reishi was significantly superior to placebo with respect to the clinical improvement of symptoms in neurasthenia.

Tang, Wenbo et al. “A randomized, double-blind and placebo-controlled study of a Ganoderma lucidum polysaccharide extract in neurasthenia.” Journal of medicinal food vol. 8,1 (2005): 53-8. doi:10.1089/jmf.2005.8.53

This study examines the effects of reishi on exhaustive exercise-induced oxidative stress in skeletal muscle tissues of mice. The mice were divided into four groups; the control group was administered with distilled water and reishi administered groups were administered with reishi. After 28 days, the mice performed an exhaustive swimming exercise, and the results provide strong evidence that reishi supplementation possesses protective effects against exhaustive exercise-induced oxidative stress.

Zhonghui, Zhao et al. “Ganoderma lucidum polysaccharides supplementation attenuates exercise-induced oxidative stress in skeletal muscle of mice.” Saudi journal of biological sciences vol. 21,2 (2014): 119-23. doi:10.1016/j.sjbs.2013.04.004

This review summarizes recent studies on the medicinal effects of edible and medicinal mushrooms, namely reishi. There are four major sites of action for the antifatigue activities of these mushrooms: For muscular function, the mushrooms mainly affect liver and muscle glycogen storage and blood lactic acid, which are the major causes for muscular fatigue. For the antioxidant effect, the mushrooms enhance the body antioxidant system by stimulating enzymes such as SOD and GSH-Px as well as limiting the detrimental effect of ROS. For the immune and hormone systems, the antifatigue function is achieved by stimulating the activities of immune cells and the expression of cytokines, as well as the testosterone. Besides these major antifatigue effects, some specific medicinal effects of edible and medicinal mushrooms also help to avoid fatigue, through improvement of liver energy state and function, blood circulation, and blood glucose regulation. Overall it’s clear that edible and medicinal mushrooms can promote the proper function and balance of the biological systems to maintain the basic harmonious pattern of body for antifatigue.

Geng, Ping et al. “Antifatigue Functions and Mechanisms of Edible and Medicinal Mushrooms.” BioMed research international vol. 2017 (2017): 9648496. doi:10.1155/2017/9648496

According to this article, stress reduction is a key aspect to reishi’s adaptogenic qualities, and it is most effective if taken on a regular basis: “The effect of ingesting reishi on a daily basis is akin to training the cardiovascular system through aerobic exercise, or training the musculoskeletal system through lifting weights. Reishi actually trains the body’s immune system and nervous system to perform better.”

Jordan, Meg. “Red Reishi: King of Adaptogens.” Global Health Media. (2007).

Immunomodulation

A number of reports have demonstrated that reishi polysaccharides modulate immune function both in vivo and in vitro. The studied immuno-modulating effects of reishi are extensive, including promoting the function of antigen-presenting cells, mononuclear phygocyte system, humoral immunity, and cellular immunity, as explained in this review.

Lin, Zhi-Bin. “Cellular and molecular mechanisms of immuno-modulation by Ganoderma lucidum.” Journal of pharmacological sciences vol. 99,2 (2005): 144-53. doi:10.1254/jphs.crj05008x

This study aimed to investigate the effects of Ganopoly (the polysaccharides extracted from reishi), on the immune function of advanced-stage cancer patients. 34 advance-stage cancer patients were treated with reishi extract 3 times daily for 12 weeks. Positive results allowed researchers to conclude that reishi enhances immune responses in patients with advanced-stage cancer.

Gao, Yihuai et al. “Effects of ganopoly (a Ganoderma lucidum polysaccharide extract) on the immune functions in advanced-stage cancer patients.” Immunological investigations vol. 32,3 (2003): 201-15. doi:10.1081/imm-120022979

The goal of this article is to investigate the effect of reishi on innate immune response. It was found, for example, that reishi stimulated TNF-alpha and IL-6 production after 8 hours of treatment in human blood. Results from this research provides supporting evidence for the immunomodulatory effects of reishi.

Wachtel-Galor, Sissi, et al. “Ganoderma lucidum (Lingzhi or Reishi).” Herbal Medicine: Biomolecular and Clinical Aspects. 2nd edition. CRC Press/Taylor & Francis, 2011.

ADDITIONAL RESEARCH

There is ongoing research on the effects of reishi as it relates to the following health concerns:

Cancer

Clinical studies have shown beneficial effects of reishi as an alternative adjuvant therapy in cancer patients. Evidence from in vitro and in vivo studies has demonstrated that GLP (the main bioactive component in the water soluble extracts of reishi) possesses potential anticancer activity through immunomodulatory, anti-proliferative, pro-apoptotic, anti-metastatic and anti-angiogenic effects.

Sohretoglu, Didem, and Shile Huang. “Ganoderma lucidum Polysaccharides as An Anti-cancer Agent.” Anti-cancer agents in medicinal chemistry vol. 18,5 (2018): 667-674. doi:10.2174/1871520617666171113121246

As an immunomodulating agent, Beta glucans (one of the active constituents of reishi) act through the activation of innate immune cells such as macrophages, dendritic cells, granulocytes, and natural killer cells. This activation triggers the responses of adaptive immune cells, resulting in the inhibition of tumor growth and metastasis. Reports have shown that Beta glucans exert multiple effects on cancer cells and cancer prevention.

Yoon, Taek Joon et al. “The effects of β-glucans on cancer metastasis.” Anti-cancer agents in medicinal chemistry vol. 13,5 (2013): 699-708. doi:10.2174/1871520611313050004

This review discusses reishi’s ability to suppress cell adhesion and cell migration of highly invasive breast and prostate cancer cells, suggesting its ability to reduce tumor invasiveness. Reishi clearly demonstrates anticancer activity in experiments with cancer cells, and has possible therapeutic potential as a dietary supplement for an alternative therapy for breast and prostate cancer.

Sliva, Daniel. “Ganoderma lucidum (Reishi) in cancer treatment.” Integrative cancer therapies vol. 2,4 (2003): 358-64. doi:10.1177/1534735403259066

In vitro and animal studies have indicated that reishi exhibits cancer-preventive and anticancer activity. Data from a clinical study in cancer patients showed Ganopoly (a reishi polysaccharide extract), enhanced immune function, including increased activity of T lymphocytes, macrophages, and natural killer cells. Several clinical studies revealed that treatment of prostate cancer patients with the reishi-containing PC-SPES (a mixture of eight herbal extracts) gave a significant decrease in the prostate-specific antigen levels, which compares favorably with second-line hormonal therapy that has agents such as estrogens and ketoconazole. Currently available data from numerous in vitro and in vivo studies suggest that the cancer-preventive and tumoricidal properties of reishi might be ascribed to its antioxidative and radical-scavenging effects, enhancement of host immune function, induction of cell-cycle arrest and apoptosis, and other biological effects.

Zhonghui, Zhao, Zheng Xiaowei, and Fang Fang. “Ganoderma lucidum polysaccharides supplementation attenuates exercise-induced oxidative stress in skeletal muscle of mice.” Saudi journal of biological sciences 21.2 (2014): 119-123.

Blood sugar control

This study investigates the hypoglycemic effects and mechanisms of action of reishi administered for 7 days in type 2 diabetic mice. Diabetes was induced by streptozotocin injection and high-fat dietary feeding. At the end of the study, fasting serum glucose, insulin, body weight and epididymal white adipose tissue weight were measured. Both doses of reishi significantly decreased fasting serum glucose, insulin and epididymal fat/body weight ratio compared with the diabetic control group.

Xiao, Chun et al. “Hypoglycemic effects of Ganoderma lucidum polysaccharides in type 2 diabetic mice.” Archives of pharmacal research vol. 35,10 (2012): 1793-801. doi:10.1007/s12272-012-1012-z

This study concludes that Proteoglycan (a protein typically found in connective tissue) from reishi is an effective antidiabetic agent because of its ability to enhance insulin secretion and decrease hepatic glucose output, along with increase of adipose and skeletal muscle glucose disposal in the late stage of diabetes. Furthermore, it is beneficial against oxidative stress, thereby being helpful in preventing the diabetic complications.

Pan, Deng et al. “Antidiabetic, antihyperlipidemic and antioxidant activities of a novel proteoglycan from ganoderma lucidum fruiting bodies on db/db mice and the possible mechanism.” PloS one vol. 8,7 e68332. 11 Jul. 2013, doi:10.1371/journal.pone.0068332

Animal studies have demonstrated that reishi has potential hypoglycemic and hypolipidemic activities. This clinical study aimed to evaluate the efficacy and safety of Ganopoly in 71 patients with confirmed type II diabetes mellitus. It was concluded that Ganopoly is efficacious and safe in lowering blood glucose concentrations

Gao, Yihuai, et al. “A phase I/II study of Ling Zhi mushroom Ganoderma lucidum (W. Curt.: Fr.) Lloyd (Aphyllophoromycetideae) extract in patients with type II diabetes mellitus.” International Journal of Medicinal Mushrooms 6.1 (2004).

Liver function

This study examines the effects of reishi on [Cd(II)]-induced hepatotoxicity in mice and the mechanism of the protection. During the study, mice were pretreated with reishi for 7 days, and subsequently challenged with a hepatotoxic (toxic to the liver) dose of Cd(II). Liver injury was evaluated 8 hours later. In summary, reishi proved to be effective in protection against Cd(II)-induced hepatotoxicity.

Jin, Hai et al. “Protective effects of Ganoderma lucidum spore on cadmium hepatotoxicity in mice.” Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association vol. 52 (2013): 171-5. doi:10.1016/j.fct.2012.05.040

This study concludes that the hepatic and renal protective mechanism of reishi might be due at least in part to its prominent superoxide scavenging effect. Reishi extract could therefore protect the liver and kidney from superoxide induced hepatic and renal damages.

Shieh, Y H et al. “Evaluation of the hepatic and renal-protective effects of Ganoderma lucidum in mice.” The American journal of Chinese medicine vol. 29,3-4 (2001): 501-7. doi:10.1142/S0192415X01000526

This article highlights the hepatoprotective activity of reishi, with an emphasis on the possible biochemical mechanisms. Preclinical studies demonstrated that reishi extracts protected the liver against injury caused by exposure to toxic chemicals. A randomized placebo-controlled clinical trial showed that treatment with reishi for 12 weeks significantly decreased hepatitis B e antigen (HbeAg) and HBV DNA levels in 25% of patients with HB.

Gao, Yihuai, et al. “Protective effect of Ganoderma (a mushroom with medicinal properties) against various liver injuries.” Food reviews international 21.1 (2005): 27-52.

Allergies

This study examines the anti-allergic constituents in reishi. It was revealed that one of the active constituents – cyclooctasulfur – effectively inhibited histamine release from rat cells, for example. It is indicated that cyclooctasulfur induced some changes in protein bands obtained from the membrane fraction of mast cells, suggesting that this compound interacts with membrane proteins so as to inhibit 45Ca uptake, and that this may be the main cause of histamine release inhibition.

Tasaka, K et al. “Anti-allergic constituents in the culture medium of Ganoderma lucidum. (I). Inhibitory effect of oleic acid on histamine release.” Agents and actions vol. 23,3-4 (1988): 153-6. doi:10.1007/BF02142526

This review explores the use of reishi in the management of histamine mediated allergic responses. A study was carried out to assess the efficacy of non- fractionalised reishi supplementation in two hay fever patients. In both cases there was a rapid and significant alleviation of symptoms on commencement of supplementation with reishi, indicating that reishi supplementation may have a role in the management of histamine-mediated immune responses, and could play a major role in current treatment practices for histamine-mediated allergic response.

Powell, Martin. “The use of Ganoderma lucidum (Reishi) in the management of histamine-mediated allergic responses.” Townsend Letter: The Examiner of Alternative Medicine 274 (2006): 78-82.