7 Incredible Health Benefits of Reishi Mushroom
Mushrooms are particularly fascinating foods, particularly because they are so different from the vast majority of things we normally consume. Plants and animals probably make up nearly 100% of most people’s diets, but mushrooms are not technically plants — they are fungi. Unlike plants, their cell walls are structured differently and they do not photosynthesize. While many fungi are microscopic, they are visible when they develop into large molds or fruiting bodies. The most iconic manifestation of a fruiting body is the stem and cap appearance, as seen in most culinary mushrooms, although different species of mushroom produce various types of fruiting bodies. Reishi mushrooms have a particularly beautiful appearance; to me, they look like a combination between a butterfly wing and a seashell. This beauty reflects the powerful compounds present in reishi and may help explain why this particular mushroom has been revered throughout history.
What is Reishi?
The scientific name for reishi is Ganoderma lucidum, although it also referred to as Ganoderma lingzhi . Reishi is unusual in that its taxonomic categorization is considered “chaotic”; a 2018 study determined that the G. lucidum variety has limited native distribution in Europe and China, while G. lingzhi is native to Asia and is the species that is apparently the most widely cultivated and sold. However, virtually all the scientific studies referenced here specifically refer to G. lucidum, and most products list that term instead of G. lingzhi, so until a more definite categorization is made, G. lucidum is arguably the best formal name for reishi. Regardless of this confusion, high-quality products labeled as reishi are certain to contain beneficial compounds and come from the Ganoderma genus overall.
Reishi has been used as a medicinal mushroom for over 2000 years, and is especially revered in China. The Chinese name lingzhi represents the concepts of spiritual potency and immortality, as well as being a symbol of success, well-being, and longevity. The first pharmacopoeia in China recommended reishi to help strengthen heart function, improve memory, enhance energy, and slow aging. Modern research has unveiled the mechanisms by which reishi contributes to health. While it cannot grant users literal immortality, there is little doubt that reishi can significantly improve the lives of consumers and may help alleviate some serious conditions. Given that the global reishi market was over $3 billion in 2019, and is expected to reach $5 billion by 2027, there is clearly high demand for this particular mushroom.
Nutrients in Reishi
The benefits of reishi are conveyed by the incredible variety of nutrients present. The dominant macronutrients in reishi are fiber and carbohydrates, accounting for 59% and 26–28% of those nutrients. Smaller amounts of fat and protein are also present, with lysine and leucine being the primary amino acid constituents. There are many classes of bioactive compounds present in reishi, including phenols, steroids, terpenoids, nucleotides, polysaccharides, and glycoproteins. Relatively heavy types of terpenoids known as triterpenoids are present and appear to be responsible for some of reishi’s effects. The effects of both whole reishi and some of the isolated components are described below.
Health Benefits of Reishi
1. Neurological Health
Mushrooms in general are reported to have significant benefits for the nervous system, and reishi is no exception. The powerful effects of reishi on neurological health have been demonstrated in numerous studies. First, a comparative study between reishi and carob on fibromyalgia symptoms was carried out in 2015 at the University of Extremadura in Spain. Fibromyalgia is not well understood, but disruptions in central nervous system activity are thought to contribute to symptoms like pain, insomnia, stiffness, and overall low quality of life. The study found that 6g of reishi per day for 6 weeks improved flexibility, speed, and aerobic endurance, while the same dose of carob powder was ineffective. The researchers concluded, “These results may indicate that Ganoderma lucidum might be a useful dietary supplement to enhance physical performance of the patients suffering from fibromyalgia.”
As noted earlier, the triterpenoids present in reishi appear to be especially powerful components. A 2020 preclinical study tested reishi triterpenoids in mouse and cell models of Alzheimer’s disease, and determined the compounds effectively reduced cognitive impairment in mice. Damage to the mouse brains was limited with triterpenoid administration, through the actions of protecting neurons, reducing oxidative damage, and inactivating harmful proteins. On the cell level, the reishi compounds promoted cell proliferation, increased levels of the endogenous antioxidant superoxide dismutase, and inhibited markers of oxidative stress including malondialdehyde and lactic dehydrogenase.
Neurasthenia is a condition characterized primarily by fatigue, and accompanied by other issues like headaches, irritability, and insomnia. The cause is uncertain and likely complex, but appears related to issues with the nervous system. A 2005 double-blind, placebo-controlled trial followed Chinese patients with neurasthenia and provided them with 1,800mg reishi three times per day for 8 weeks. Overall severity of the condition was reduced by 15.5% and sense of fatigue was reduced by 28.3% in the reishi group. The researchers concluded, “[Reishi] was significantly superior to placebo with respect to the clinical improvement of symptoms in neurasthenia.”
2. Immune Health and Anti-Inflammatory Properties
Polysaccharides are another category of reishi compounds with substantial biological activity. A 2010 study published in the journal Bioorganic & Medicinal Chemistry determined that a polysaccharide extract of reishi could enhance the survival and renewal abilities of blood stem cells, as well as promote growth of white blood cells. The researchers noted these properties could help reduce disease progression and improve health.
A review article published in 2019 summarized the wide-ranging effects of reishi on the immune system. Based on cell and animal studies, the researchers noted that reishi has been shown to promote innate immunity, the release of antibodies, and cellular immunity overall. The polysaccharides in particular are associated with promoting the function of macrophages, natural killer cells, B and T lymphocytes, and dendritic cells, in part by modulating the release of cytokines (cell signaling proteins). Lipids from the spores of reishi have also been shown to increase white blood cells and platelets in mice treated with chemotherapy.
A double-blind, placebo-controlled trial conducted by researchers at multiple universities in Columbia discovered immune-boosting benefits from the beta-glucan portion of reishi. Beta-glucans are the chief polysaccharide molecules found in reishi, and are essentially specially-organized chains of glucose. In the study, children between the ages of 3 and 5 received yogurt containing beta-glucans or placebo. After 12 weeks, those receiving the reishi-derived treatment had significantly higher blood levels of numerous T-cell types. The authors noted these immune cells are critical for defense against infectious threats, and more studies are warranted to examine the practical impact of preventing infections.
Reishi appears to have adaptogenic properties, being able to stimulate the immune system in some circumstances while acting as an anti-inflammatory in others. A 2017 study in the Journal of Neuroinflammation reported that reishi polysaccharides were able to reduce chemical-induced neuroinflammation in experimental cell models. The reishi compounds reduced pro-inflammatory cytokines, increased anti-inflammatory cytokines, and inhibited immune cell migration. It was theorized that the neuroprotective function of reishi is based at least in part on these anti-inflammatory effects.
Asthma is largely driven by uncontrolled inflammation, and reishi compounds may play a role in treating asthma via anti-inflammatory effects. In a 2020 study in the Journal of Leukocyte Biology, a specific protein from reishi, known as rLZ-8, was found to reduce lung inflammation in mice with chemical-induced asthma. Specifically, infiltration of immune cells like eosinophils and dendritic cells decreased, the exceptionally powerful pro-inflammatory cytokine IL-17A decreased, and the anti-inflammatory cytokine IL-10 increased. Inflammatory T-cells were also reduced while anti-inflammatory, regulatory T-cells were enhanced.
More research on just reishi and asthma is needed, but its potential efficacy in humans was suggested by a double-blind, placebo-controlled trial in which reishi was given alongside two other herbs, Ku-Shen and Gan-Cao, and compared to prednisone. The herbal combination effectively improved lung function, reduced symptoms, and limited the need for bronchodilators. Modulation of inflammatory cytokines was associated with these benefits. The prednisone group experienced slightly better lung function improvement, but also caused an adverse effect on adrenal function.
Inflammation and associated damage to neurons is a key process in the development of Parkinson’s disease. A preclinical study carried out in 2011 found that reishi downregulated production of inflammatory and cytotoxic compounds, including tumor necrosis factor-α, interleukin-1β, and nitric oxide, which contributed to the protection of neurons involved in the production of dopamine.
3. Bone Health
While mushrooms in general are not usually associated with supporting bone health, this may change as more research emerges. To start, a 2020 study by researchers with Jilin University in China found that the reishi protein rLZ-8 helped treat steroid-induced osteoporosis in rats. Specifically, bone loss was prevented and structural deterioration was reduced. LZ-8 modified the ratio of proteins called OPG and RANKL to impede the formation of cells that break down bone, and not only prevented damage but helped reverse it. Researchers concluded, “Our results suggested that rLZ-8 may be developed into promising anti-osteoporosis drug with both preventive and therapeutic properties.” Of course, human research is needed to confirm if this effect translates.
Lipids derived from reishi spores may also be relevant to protecting bones. A 2019 study published in Biotechnology Progress found that the spore lipids improved the ability of stem cells to differentiate into bone-promoting cells. Furthermore, the lipids were found to help protect cells from chemotherapeutic toxicity, including stopping stem cells from dying.
4. Kidney and Liver Health
The antioxidant properties of compounds in reishi are relevant to protecting the kidneys. A 2020 study in the International Journal of Medicinal Mushrooms found that administering reishi along with a toxic chemical to animals reduced kidney damage and prevented the loss of endogenous antioxidants caused by the chemical. Another 2020 study with rats determined that reishi administration countered the kidney damage caused by chemotherapy, through a combination of antioxidant, anti-inflammatory, and anti-apoptotic (programmed cell death) effects. Inhibiting the actions of epidermal growth factor receptor (EGFR) was also found to contribute to the benefits of reishi.
Diabetic nephropathy is a kidney condition that can emerge in diabetic patients and contribute to health problems. In 2014, researchers discovered a new proteoglycan (protein and sugar) compound in reishi they called FYGL, then tested it on diabetic mice. There were widespread beneficial effects, including reductions in blood sugar concentrations, kidney/body weight ratio, and levels of other harmful compounds. Antioxidant enzymes in the kidneys, such as superoxide dismutase, glutathione peroxidase, and catalase, all were increased. Even abnormalities in the shape of the kidneys were improved. Researchers concluded, “FYGL confers protection against the renal functional and morphologic injuries by increasing activities of antioxidants and inhibiting accumulation of oxidation.”
Heavy metal build-up in the kidneys can cause health problems, so the fact that a 2019 study revealed reishi could reduce lead in rat kidneys is certainly promising. Lead levels in the liver were also reduced, as were levels of proteins in blood serum that reflect liver injury. Antioxidant enzymes that were inhibited by lead were restored by reishi.
The benefits of reishi for healthy individuals was examined in a placebo-controlled trial conducted by researchers in China and Russia. After six months of using 225mg reishi per day, participants underwent several tests including a ultrasonic scan which revealed the reversal of mild fatty liver and reductions in markers of damaged liver health, such as thiobarbituric acid reactive substances. Furthermore, participants in the reishi group had enhanced activation of antioxidant enzymes and more improved total antioxidant capacity than those in the placebo group.
5. Skin Health and Wound Healing
A number of preclinical studies point to the potential of reishi to protect skin and accelerate wound healing. A 2019 study by a team of researchers in China and the United States examined the impact of reishi polysaccharides on isolated human skin fibroblasts as well as mice with surgically-induced wounds. Fibroblasts are cells that secrete collagen proteins and help maintain connective tissues; they also facilitate wound healing. Polysaccharides were found to support these cells by increasing their viability, enhancing migration, and upregulating a growth factor compound. In mice given the polysaccharides, the rate of wound healing was significantly faster than in the control group.
Exposure to ultraviolet (UV) rays from the sun, both UVA and UVB, is well known to contribute to skin cell damage and even potentially lead to skin cancers. A 2017 study showed that reishi polysaccharides could counter UVB-induced damage to human skin fibroblasts by increasing their viability, reducing reactive oxygen species, and modulating protein expression, with the ultimate outcome of decreasing the number of aged cells.
Another study on reishi polysaccharides and UVB damage, published in 2019 in the Journal of Cellular Physiology, further confirmed the ability of the compounds to prevent damage from UVB-radiation, including inhibiting skin pigmentation in zebrafish and erythema (reddening of the skin) in guinea pig skin. The benefits were partially delivered via the ability of the polysaccharides to protect mitochondria from oxidative damage.
Keratinocytes are the most common type of cell in human skin, and evidence suggests reishi compounds can affect these cells in positive ways. A 2020 study by researchers with multiple universities in Italy determined that reishi extract could facilitate the growth of cultured keratinocytes by increasing the expression of proteins involve in the cell cycle. Activation of proteins involved in tissue remodeling was also increased. Antioxidant and neuroprotective effects further contributed to the benefits of the reishi extract. The researchers noted that reishi may be able to accelerate healing processes through the effects documented in this study.
Reishi spore oil is a particularly powerful product derived from reishi and is high in triterpenoids. A 2020 study in the journal Aging tested the spore oil on mice with burn wounds, and found that not only did the oil accelerate healing, but it did so in part by regulating levels of bacteria on the skin surface. Reduction of numerous inflammatory cytokines also played a role in reishi spore oil’s benefits.
6. Cardiovascular Health and Blood Sugar Regulation
Some evidence suggests reishi can exert positive effects on measures of cardiovascular health, although more research on this front is especially needed. A 2012 double-blind, placebo-controlled study in the British Journal of Nutrition gave 1.44g reishi per day for 12 weeks to people with mild hypertension or high cholesterol/lipids. This intervention resulted in lower insulin levels and less insulin resistance, as well as higher levels of the good HDL cholesterol.
Another trial examined the impact of beta-glucans derived from reishi on patients with high risk and stable angina (chest pain caused by reduced blood flow to the heart). 750mg of beta-glucans per day for 90 days increased superoxide dismutase antioxidant levels, suppressed malondialdehyde levels (a measure of oxidative stress), and reduced the number of circulating endothelial cells (a measure of blood vessel damage).
7. Urinary Tract Health
While the dose utilized was tremendously low, a double-blind, placebo-controlled trial showed that just 6mg of reishi extract per day for 12 weeks could reduce symptoms of an impaired lower urinary tract. While physical measures of urinary tract health were unchanged, symptoms related to urination like frequency and urgency improved, as measured by the International Prostate Symptom Score scale.
Other Potential Benefits of Reishi
Anti-Aging Effects
One of the purported uses of reishi mushrooms is to fight the aging process. This has not been supported by any human trials, but the preclinical evidence is intriguing, and it makes sense to include reishi as part of a holistic protocol to support overall health and potentially combat the aging process. A review article from 2019 by researchers with Peking University in China stated that reishi may help extend life due to its immunoregulatory and antioxidant properties. Reishi has been shown to inhibit formation of reactive oxygen species and lipid peroxidation, as well as reduce levels of advanced oxidation protein products. It can also increase levels of the endogenous antioxidants glutathione, superoxide dismutase, and catalase in preclinical models. Conducting research on general life extension in humans is especially difficult, but it would be amazing if one day reishi really were shown to help people live longer.
It is notable that a 2004 double-blind, placebo-controlled trial conducted at Hong Kong Polytechnic University showed that a single dose of 1.1g reishi resulted in increased blood antioxidant levels 90 minutes after ingestion. 3 hours after ingestion, there was a 29% average increase in antioxidant capacity measured in urine. 10 days of supplementation with .72g reishi per day also improved blood and urine antioxidant levels. Given the importance of antioxidants in countering disease development and potentially slowing aging, these results are interesting.
Anti-Viral Effects
Certain compounds in reishi, especially the triterpenoids, may have value for fighting viruses. For example, a 2019 study from a diverse team of researchers in Korea, India, and Turkey found that the reishi triterpenoid known as ganodermanontriol inhibited dengue virus infection of isolated cells. More importantly, a clinical trial conducted in 2014 compared a combination of reishi and turkey tail mushroom with the Laetiporus sulphureus mushroom (also known as chicken of the woods). It found that 88% of participants taking the reishi/turkey tail combination for 2 months experienced clearance of the virus, while only 5% of participants in the Laetiporus group experienced clearance. Unfortunately, it is impossible to quantity the specific impact of reishi and turkey tail since they were used together, but it is likely that reishi was responsible for at least some of the efficacy determined in this study.
Another study in 2007 pointed to the ability of reishi to shorten the duration of herpes genitalis and herpes labialis symptoms. However, reishi was only one of six components of the herbal medicine tested, and the dose and administration method were unclear. Again, more research is needed with reishi as a sole treatment to fully understand its anti-viral potential.
While efficacy in humans is quite uncertain, a very interesting study carried out in part by Paul Stamets, the legendary mushroom researcher and founder of the Host Defense brand of mushroom products, found that extracts of reishi mycelium exhibited antiviral effects on viruses that affect bees. In treated bee colonies, the extract led to a 79-fold reduction in honey bee deformed wing virus and a 45,000-fold reduction in Lake Sinai virus, compared to control colonies. Of further interest, bees have been naturally observed foraging on mushroom mycelium, indicating they may be deliberately seeking out fungi-derived nutrients for their own protection.
Reishi for Cancer Treatment
Medicinal mushrooms including reishi are often touted as alternative cancer treatments. There are indeed numerous preclinical studies showing that compounds in reishi can inhibit the growth of cancer cells. However, the human research is far from conclusive. A 2016 review article summarized the results from five randomized clinical trials that examined the impact of reishi on cancer progression in human patients. While the study authors noted that the trials’ methodology was unsatisfying, it was determined that patients who used reishi alongside chemotherapy or radiation were more likely to respond positively to treatment than those who used conventional therapies alone. The activity of certain white blood cells including natural killer cells was slightly elevated in reishi groups, and most of the studies also revealed improved quality of life. For example, a 2003 clinical trial with reishi polysaccharides found that treatment of advanced cancer patients for 12 weeks resulted in beneficial modulation of cytokines, immune cells, and natural killer activity, leading to the conclusion that the intervention “enhanced the immune responses in patients with advanced-stage cancer.”
It is more conclusive that reishi plays a role in supporting quality of life for cancer patients. A 2012 trial with breast cancer patients found that 4 weeks of treatment with reishi spore powder improved physical well-being and reduced fatigue, in addition to lowering markers of inflammation.
Ultimately, the evidence was clear that reishi should not be used as a sole, primary treatment for cancer. The authors did note that reishi could be considered as an adjunct to conventional treatment due to the possibility it could enhance tumor response and stimulate immunity, with virtually no risk of toxicity and little risk of side effects.
Improving Vaccine Efficacy
A particularly interesting use for reishi is potentially boosting the efficacy of vaccines by acting as an adjuvant. Adjuvants are compounds included in vaccines to stimulate a greater immune response to the primary antigen. A 2011 study in the journal Human Vaccines described how the rLZ-8 protein from reishi increased effectiveness of a DNA vaccine in a preclinical tumor model. DNA vaccines are not currently used in humans, but if they are eventually approved, reishi compounds may end up being included as part of the formula.
Conclusion
Reishi is a truly fascinating mushroom that deserves its status as a revered medicinal product. In addition to conventional benefits for humans, its potential applications for helping protect bees from viruses and improving vaccine efficacy are quite exciting.
