Ganoderma lucidum (G. lucidum), also known as Reishi in Japanese Medicine or Lingzhi in Chinese Medicine, is a large, dark mushroom from Asian Traditional Medicine that has been praised for its powerful health benefits for over 2,000 years. The fruiting body with its glossy exterior and woody texture, along with mycelia and spores, are the components of the mushroom used as medicine.
In the years before cultivation, G. lucidum was rare and primarily consumed by the rich and privileged members of Chinese society. It was believed that the sacred mushroom grew in the home of the immortals off the coast of China, hence gaining the title ‘mushroom of immortality,’ symbolizing success and longevity. Several works of art including paintings, carvings, furniture and even women’s accessories depict the mushroom, highlighting its reputation as a sacred fungus.
While some of the earliest references of G. lucidum are found in scripts from the second to sixth centuries, it wasn’t until the Ming Dynasty in the sixteenth century when the mushroom was associated with therapeutic value, as described in the very first Chinese Pharmacopeia. Properties included enhanced vital energy, memory, cardiac function, and tonifying and anti-aging effects.
According to the State Pharmacopoeia of the People’s Republic of China, G. lucidum acts to replenish Qi, calm the mind and reduce coughing and asthma. It is also recommended for insomnia, dizziness, shortness of breath and heart palpitations. Since the early 1970’s, cultivation of G. lucidum has become a major source of the mushroom, with popularity extending outside of Asian Traditional Medicine and into the West.
Reishi mushrooms, as they are typically referred to in the West, are made up of 90% water by weight. The remaining 10% is rich in protein, dietary fiber and contains various trace minerals and vitamins, with potassium, calcium, phosphorus, magnesium and selenium accounting for most of the mineral content. All of these play a role in the many reported health benefits of reishi mushrooms.
The medicinal mushrooms contain a wide variety of bioactive molecules, with polysaccharides, peptidoglycans and triterpenoids being the major and most researched constituents. Polysaccharides, which are sub-divided into β-1,3-glucans and polysaccharide peptides like peptidoglycans, are reported to demonstrate a wide range of activities. These include antiinflammatory, anticancer, antiulcer, hypoglycemic (sugar regulating) and most notably, stimulating the production of immune cells—with the latter driven by the activity of β-1,3-glucans. Triterpenes, which are found in high quantities in the mushroom and are responsible for their bitter taste, have been shown to exhibit lipid-lowering and antioxidant properties.
When looking at effective therapeutic applications, the desired goal is to offer value with little to no toxicity. Research to date on the therapeutic potential of reishi mushrooms demonstrates its role in relation to chronic diseases like cancer and diabetes, as well as viral and bacterial infections and liver disease.
To date, there is considerable evidence supporting the immune cell stimulating effects of reishi, which could result in improved protection against invaders and the removal of dangerous or cancerous cells. The antioxidant effects of polysaccharides and triterpenes in reishi have also been demonstrated in in vitro (outside of organism) studies, owing largely to the rich polyphenolic content in these molecules. Antioxidants offer protection against oxidative damage, which is likely to reduce the risk of mutations and cancer, and also protect cells of the immune system so they can continue to work efficiently.
Hundreds of plant species, including mushrooms, have been studied in the search for preventative and therapeutic agents against cancer. Many polysaccharides and triterpenes in reishi have been shown to demonstrate anticancer, or more specifically, antitumor activity, in vitro and in vivo (inside organism) studies through various mechanisms of action, including inhibiting or down-regulating critical enzymes involved in cancer cell growth. Promising antitumor activity has been demonstrated in several cancer cell lines, including prostate, colon, breast and lung.
Randomized, controlled trials on cancer patients supplementing with reishi have also demonstrated positive outcomes. In one trial, patients with advanced cancers of different types were supplemented with a dosage of 1800 mg/day of reishi for 12 weeks. In 80% of patients, there was a significant increase in levels of key immune cells, including interleukin (IL)-2, IL-6, and interferon γ (IFN-γ) levels, as well as natural killer (NK) cell activity.
Another human trial by the same research group looked at lung cancer patients supplementing with reishi and also showed significantly increased levels of immune cells in the reishi-treated group, along with increased quality of life scores in 65% of patients. These results provide some evidence that the anti-cancer properties of reishi are associated with its effects on the immune system.
The inhibition of viral and bacterial multiplication is another area of reishi mushroom research. This is due to two factors: 1) the need for new agents with less side effects; and 2) the rise of resistant and mutant strains in response to current therapies. Current in vitro research demonstrates the inhibited replication of herpes simplex virus type 1 (HSV-1), herpes simplex virus type 2 (HSV-2), human immunodeficiency virus (HIV)-1 and hepatitis B virus. However, further research is needed to understand the mechanisms of action.
Small trials on patients with varicella zoster virus, which causes chicken pox and shingles, have also reported beneficial effects of the mushroom taken orally, however additional studies are needed to validate results. In vitro and in vivo studies have also been done with reishi to explore its antibacterial potential, with inhibitory effects demonstrated against multiple bacterial strains. While promising preliminary data exists, further research is required for both antiviral and antibacterial studies.
Components of reishi have also been shown to have hypoglycemic or blood glucose modulating effects in animal studies, either alone or in combination with conventional treatments. Reishi has also demonstrated protection against liver and gastric injuries in animal studies, through several different mechanisms of action.
While there are now several published reports on reishi with some promising preliminary data, the majority are based on in vitro and in vivo studies. There are also some reported human trials, however, they are small and currently there is still no cohesive body of research. This is due to a range of factors from dosage to production quality, highlighting the need for a standardized approach to improving quality control procedures.
Overall, more research from well-designed in vitro, in vivo and human clinical studies is needed across various therapeutic areas. Until then, scientific assessment on the impact of this 2,000 year old traditional therapy on human health remains to be established.
As the popularity of this sacred fungus continues to grow and spread across the West, there are several safety considerations to keep in mind before taking the supplement. Reishi supplements may cause anticoagulants or antiplatelets to become more effective, which increases the risk of bleeding. It is therefore not recommended for people scheduled for surgery or by sufferers of bleeding disorders.
Reishi might also lower blood pressure and is best avoided by those with low blood pressure or by those who are currently taking blood pressure medication. This guidance also applies to people taking immunosuppressants, as the supplements may counteract their effectiveness.
Finally, women who are pregnant or breastfeeding should not consume these mushrooms as there is not enough data on the impact of reishi supplements on this group. If you are curious about taking the mushroom as adjunct therapy, please consult with your medical doctor or chemotherapist. For those with pre-existing health conditions, it is always recommended to do research and seek guidance first, versus self-experiment.
On a personal note, I have been consuming reishi supplements in tincture, capsule and tea form on and off for the past decade, with no interest in ending my routine. It is rare to come across over-the-counter supplements that show promise for a wide variety of mechanisms, including anti-cancer, immune system modulation and blood sugar regulation. I remain hopeful in the healing potential of reishi, and look forward to uncovering deeper insights about the mechanisms of action of this sacred mushroom of immortality in well-designed studies in the years to come.
- Wachtel-Galor S, Yuen J, Buswell JA, et al. Ganoderma lucidum (Lingzhi or Reishi): A Medicinal Mushroom. Herbal Medicine: Biomolecular and Clinical Aspects. 2nd edition. 2011.
- Wasser S. P, Coates P, Blackman M, Cragg G, Levine M, Moss J, White J. Encyclopedia of Dietary Supplements. New York: Marcel Dekker; 2005. Reishi or Lingzhi (Ganoderma lucidum) pp. 680–90.
- The State Pharmacopoeia Commission of P. R. China. State Pharmacopoeia Commission of the People’s Republic of China. Beijing, China: Chemical Industry Press; 2000.
- McMeekin D. The perception of Ganoderma lucidum in Chinese and Western culture. Mycologist. 2005;18:165–9.
- Wachtel-Galor S, Buswell J. A, Tomlinson B, Benzie I. F. F. Lingzhi polyphorous fungus. In: Herbal and Traditional Medicine: Molecular Aspects of Health. New York: Marcel Dekker Inc; 2004. pp. 179–228.
- Chang S. T, Buswell J. A. Ganoderma lucidum (Curt.: Fr.) P. Karst. (Aphyllophoromycetideae): A mushrooming medicinal mushroom. Int J Med Mushrooms. 1999;1:139–46.
- Borchers A. T, Stern J. S, Hackman R. M, Keen C. L, Gershwin M. E. Minireview: Mushrooms, tumors and immunity. Proc Soc Exp Biol Med. 1999;221:281–93.
- Boh B, Berovic M, Zhang J, Zhi-Bin L. Ganoderma lucidum and its pharmaceutically active compounds. Biotechnol Annu Rev. 2007;13:265–301.
- Zhou X, Lin J, Yin Y, Zhao J, Sun X, Tang K. Ganodermataceae: Natural products and their related pharmacological functions. Am J Chin Med. 2007;35:559–74.
- Miyazaki T, Nishijima M. Studies on fungal polysaccharides. XXVII. Structural examination of a water-soluble, antitumor polysaccharide of Ganoderma lucidum. Chem Pharm Bull. 1981;29:3611–16.
- Mallard B, Leach D. N, Wohlmuth H, Tiralongo J. Synergistic immuno-modulatory activity in human macrophages of a medicinal mushroom formulation consisting of Reishi, Shiitake and Maitake. PLoS ONE. 2019;14(11).
- Tomoda M, Gonda R, Kasahara Y, Hikino H. Glycan structures of ganoderans B and C, hypoglycemic glycans of Ganoderma lucidum fruit bodies. Phytochemistry. 1986;25:2817–20.
- Li Z, Liu J, Zhao Y. Possible mechanism underlying the antiherpetic activity of a proteoglycan isolated from the mycelia of Ganoderma lucidum in vitro. J Biochem Mol Biol. 2005;38(1):34–40.
- Ji Z, Tang Q, Zhang J, Yang Y, Jia W, Pan Y. Immunomodulation of RAW264.7 macrophages by GLIS, a proteopolysaccharide from Ganoderma lucidum. J Ethnopharmacol. 2007;112:445–50.
- Chen D. H, Shiou W. Y, Wang K. C, editors. et al. Chemotaxonomy of triterpenoid pattern of HPLC of Ganoderma lucidum and Ganoderma tsugae. J Chin Chem Soc. 1999;46:47–51.
- Su C. H, Yang Y. Z, Ho H, Hu C. H, Sheu M. T. High-performance liquid chromatographic analysis for the characterization of triterpenoids from Ganoderma. J Chromatogr Sci. 2001;39:93–100.
- Wasser S. P, Weis A. L. Medicinal properties of substances occurring in higher basidiomycetes mushrooms: Current perspectives. Int J Med Mushrooms. 1999;1:31–62.
- Borchers A. T, Krishnamurthy A, Keen C. L, Meyers F. J, Gershwin M. E. The immunobiology of mushrooms. Exp Biol Med. 2008;233:259–76.
- Min B. S, Gao J. J, Nakamura N, Hattori M. Triterpenes from the spores of Ganoderma lucidum and their cytotoxicity against meth-A and LLC tumor cells. Chem Pharm Bull. 2000;48:1026–33.
- Jiang J, Slivova V, Valachovicova T, Harvey K, Sliva D. Ganoderma lucidum inhibits proliferation and induces apoptosis in human prostate cancer cells PC-3. Int J Oncol. 2004;24:1093–9.
- Cao Q. Z, Lin Z. B. Ganoderma lucidum polysaccharides peptide inhibits the growth of vascular endothelial cell and the induction of VEGF in human lung cancer cell. Life Sci. 2006;78:1457–63.
- Hong K. J, Dunn D. M, Shen C. L, Pence B. C. Effects of Ganoderma lucidum on apoptotic and anti-inflammatory function in HT-29 human colonic carcinoma cells. Phytother Res. 2004;18:768–70.
- Jiang J, Grieb B, Thyagarajan A, Sliva D. Ganoderic acids suppress growth and invasive behavior of breast cancer cells by modulating AP-1 and NF-kappaB signaling. Int J Mol Med. 2008;21:577–84.
- Gao Y. H, Zhou S. F, Jiang W. Q, Huang M, Sai X. H. Effects of Ganopoly (a Ganoderma lucidum polysaccharide extract) on immune functions in advanced-stage cancer patients. Immunol Invest. 2003;32:201–15.
- Gao Y. H, Sai X. H, Chen G. L, Ye J. X, Zhou S. F. A randomized, placebo-controlled, multi-center study of Ganoderma lucidum (W. Curt.: Fr.) Lloyd (Aphyllophoromycetideae) polysaccharides (Ganopoly) in patients with advanced lung cancer. Int J Med Mushrooms. 2003;5:368–81.
- Wang S. Y, Hsu M. L, Hsu H. C, editors. et al. The anti-tumor effect of Ganoderma lucidum is mediated by cytokines released from activated macrophages and T lymphocytes. Int J Cancer. 1997;70:699–705.
- Kuo M. C, Weng C. Y, Ha C. L, Wu M. J. Ganoderma lucidum mycelia enhance innate immunity by activating NF-kappaB. J Ethnopharmacol. 2006;103:217–22.
- Lee J. M, Kwon H, Jeong H, editors. et al. Inhibition of lipid peroxidation and oxidative DNA damage by Ganoderma lucidum. Phytother Res. 2001;15:245–9.
- Mau J. L, Lin H. C, Chen C. C. Antioxidant properties of several medicinal mushrooms. J Agric Food Chem. 2002;50:6072–7.
- Mohsin M, Negi P, Ahmed Z. Determination of the antioxidant activity and polyphenol contents of wild Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt. Fr.) P. Karst. (higher Basidiomycetes) from central Himalayan hills of India. Int J Med Mushrooms. 2011;13(6):535-44.
- El-Mekkawy S, Meselhy M. R, Nakamura N, editors. et al. Anti-HIV-1 and anti-HIV-1-protease substances from Ganoderma lucidum. Phytochemistry. 1998;49:1651–7.
- Oh K. W, Lee C. K, Kim Y. S, Eo S. K, Han S. S. Antiherpetic activities of acidic protein bound polysaccharide isolated from Ganoderma lucidum alone and in combination with Acyclovir and Vidarabine. J Ethnopharmacol. 2000;72:221–7.
- Liu J, Yang F, Ye L. B, Yang X. J, Timani K. A, Zheng Y, Wang Y. H. Possible mode of action of antiherpetic activities of a proteoglycan isolated from the mycelia of Ganoderma lucidum in vitro. J Ethnopharmacol. 2004;95:265–72.
- Hijikata Y, Yamada S. Effect of Ganoderma lucidum on postherpetic neuralgia. Am J Chin Med. 1998;26:375–81.
- Hikino H, Konno C, Mirin Y, Hayashi T. Isolation and hypoglycemic activity of ganoderans A and B, glycans of Ganoderma lucidum fruit bodies. Planta Med. 1985;4:339–40.
- Lin J. M, Lin C. C, Chen M. F, Ujiie T, Takada A. Radical scavenger and antihepatotoxic activity of Ganoderma formosanum, Ganodermalucidum and Ganoderma neo-japonicum. J Ethnopharmacol. 1995;47:33–41.
- Gao Y, Tang W, Gao H, Chan E, Lan J, Zhou S. Ganoderma lucidum polysaccharide fractions accelerate healing of acetic acid-induced ulcers in rats. J Med Food. 2004;7(4):417–21.
- Lai T, Gao Y, Zhou S. Global Marketing of Medicinal Ling Zhi Mushroom Ganoderma lucidum (W.Curt.:Fr.) Lloyd (Aphyllophoromycetideae) Products and Safety Concerns. Intl J Med Mush. 2004;6(2).
- Wicks SM, Tong R, Wang CZ, O'Connor M, Karrison T, Li S, Moss J, Yuan CS. Safety and tolerability of Ganoderma lucidum in healthy subjects: a double-blind randomized placebo-controlled trial. Am J Chin Med. 2007;35(3):407-14.