“Lingzhi” — a treasure of Eastern medicine now validated by modern science
Reishi, called Lingzhi in Chinese ("spiritual plant"), was once so rare that it was reserved for emperors and elites. Now cultivated on a large scale, it has become one of the most studied medicinal mushrooms in the world, with more than 400 clinical and preclinical studies documented in the scientific literature.
In this article, we explore its unique composition, adaptogenic, immunomodulatory, and antioxidant properties, practical uses — and, above all, the precautions to know before incorporating it into your routine.
What is reishi?
Reishi (Ganoderma lucidum) is a woody-textured, characteristically semicircular mushroom that grows naturally on the trunks and roots of broadleaf trees — oaks, maples, and elms — in the temperate and subtropical regions of East Asia. Its shiny mahogany-brown surface with lacquered highlights has earned it the nickname "lacquer mushroom."
In traditional Chinese medicine (TCM), reishi is classified among the superior Qi tonics — substances that harmonize the body and mind, strengthen vitality, and promote longevity. Ancient texts attribute to it the ability to "calm the mind, strengthen the heart, and lengthen life."
Wild reishi is extremely rare — in the past, there was just 1 specimen for every 10,000 trees, which explained its precious nature. Today, almost all commercially available reishi is cultivated on controlled substrates (sawdust, cereal grains). Quality varies considerably depending on the species used, the part of the mushroom (cap, stem, mycelium), the fruiting body/mycelium ratio, and the extraction methods. For optimal efficacy, choose products made from the entire fruiting body (fruiting body) with a polysaccharide content of ≥ 30%.
Its unique phytochemical composition
Reishi's therapeutic richness is explained by its exceptionally complex phytochemical composition. Here are the most active molecular families.
The beta-1,3/1,6-glucans in reishi are the best-documented molecules for immunomodulation. They bind to the surface receptors of immune cells — notably Dectin-1 receptors on macrophages and dendritic cells — and activate a cascade of innate and adaptive immune responses. Unlike aggressive immunostimulants, reishi beta-glucans have a modulating effect: they strengthen the response when it is weak and regulate it when it is excessive, explaining their relevance in contexts of immunodeficiency and autoimmune tendencies.
The 3 main properties of reishi
This is the best-documented property. The polysaccharides in reishi regulate immune system activity in both directions — stimulating it in cases of weakened immunity and regulating it in cases of overactivity. This dual action distinguishes it from simple immunostimulants and makes it a particularly interesting ally in cases of recurrent fatigue, seasonal changes, or prolonged stress.
Reishi is one of the few mushrooms classified as an adaptogen—that is, capable of helping the body better withstand various forms of stress (physical, emotional, and environmental) without excessive stimulating or sedative effects. Ganoderic acids act in particular on the GABAergic system, explaining the observed effects on sleep quality and mild anxiety.
Reishi contains exceptionally high concentrations of polyphenols, triterpenes, and antioxidant polysaccharides that neutralize free radicals and protect cells from oxidative stress. These effects are particularly pronounced in the liver—the organ most exposed to toxins—which explains the traditional use of reishi as a liver tonic. Preclinical studies document a reduction in markers of liver damage following toxin exposure.
What the science says: recent studies
Here is an overview of the most recent clinical research on reishi in the three best-documented areas.
Several randomized studies have documented increased Natural Killer (NK) cell and T-lymphocyte activity in subjects supplemented with standardized reishi extract. A meta-analysis published in PLOS ONE (2016) concluded that there is moderate evidence of beneficial immunomodulation, particularly in cases of immunosuppression or chronic stress.
A randomized clinical study from 2012 (Pharmacology, Biochemistry and Behavior) showed that ganoderic acids increase total sleep time and improve deep sleep quality through an interaction with GABA-A receptors. A significant reduction in self-reported anxiety scores was observed after 4 weeks of daily use.
Shimizu et al. (2006, Journal of Ethnopharmacology) identified that the ganoderic acids in reishi inhibit 5α-reductase, an enzyme involved in the conversion of testosterone into DHT—the primary mediator of androgenetic alopecia. More recent research (Wang et al., Phytotherapy Research, 2024) confirms improved viability of dermal papilla cells in vitro.
Despite the wealth of literature on reishi, the majority of studies are preclinical (in vitro or in animal models) or involve limited clinical sample sizes. Large randomized controlled trials in humans are still lacking for certain indications. The EMA (European Medicines Agency) classifies reishi as having a well-established traditional use for immune support and relief of fatigue. It remains a natural supplement to incorporate into a healthy lifestyle, not a medicine.
How and in what form to consume reishi
Reishi is available in many dosage forms. The choice depends on your goals, lifestyle, and desired concentration of active compounds.
The most convenient and accurately dosed form. Prefer dual-extraction products (water + alcohol) to concentrate both polysaccharides and triterpenes. Ideal content: ≥ 30% polysaccharides, ≥ 10% beta-glucans.
Versatile — can be added to smoothies, broths, lattes, or culinary preparations. Pronounced bitter taste. Less concentrated than extracts; check the concentration ratio.
Traditional form. Dried slices simmered in water for 1 to 2 hours. Bitter, earthy flavor. Water extraction releases polysaccharides but not triterpenes (which are soluble in alcohol).
Rapid absorption, convenient for diluting in a drink. Hydroalcoholic tinctures offer the broadest spectrum of active compounds (polysaccharides + triterpenes).
The doses studied in clinical trials range from 1.5 g to 9 g of reishi powder per day, or the equivalent amount of concentrated extract (generally 500 mg to 1.5 g of 10:1 extract). A 6- to 12-week course is generally needed to observe significant effects on immunity and stress. It is recommended to take breaks (e.g., 8 weeks of use, 2 weeks off) and start with the minimum dose to assess individual tolerance.
Contraindications and precautions for use
Reishi is generally well tolerated at physiological doses, but several situations require particular caution or prior medical consultation.
Reishi is not recommended during pregnancy and breastfeeding due to the lack of safety studies in these situations. As a precaution, its use should be avoided or strictly approved by a doctor or midwife.
Reishi has mild anticoagulant and antiplatelet properties. When combined with medications such as warfarin, aspirin, or clopidogrel, it may potentiate the anticoagulant effect and increase the risk of bleeding. Medical consultation is imperative before taking it.
Due to its anticoagulant effect, it is recommended to stop taking reishi at least 2 weeks before scheduled surgery to avoid any increased risk of bleeding. Always inform your surgeon and anesthesiologist about the supplements you take.
Although reishi is immunomodulatory rather than simply immunostimulatory, people with autoimmune diseases (lupus, multiple sclerosis, rheumatoid arthritis) or those taking immunosuppressive treatment should consult their doctor before consuming it, as a precaution.
At high doses or with prolonged use (> 3 to 6 months without a break), reishi may cause: mild digestive discomfort, dry mouth, dizziness, or, very rarely, reversible liver reactions. These effects are generally dose-dependent and disappear when the dose is reduced or use is discontinued. Always start with the minimum recommended dose and increase gradually according to your tolerance.
FAQ — Frequently asked questions about reishi
doi.org/10.1371/journal.pone.0158337
doi.org/10.1016/j.pbb.2012.01.025
doi.org/10.1016/j.jep.2005.07.017
doi.org/10.1002/ptr.8159
doi.org/10.1002/14651858.CD007731.pub3
Gynecologist practicing in Paris for 18 years, specialized in women's hormonal health, perimenopause and menopause. At Nutremys LAB, she brings her medical perspective to every product we offer.
Learn more about Dr. Mariam E.K. →The information shared on this blog is for educational and informational purposes only. It does not replace medical consultation, diagnosis or treatment prescribed by a healthcare professional. If you have symptoms, are undergoing treatment or are pregnant, consult your doctor before modifying your diet or starting supplementation. Nutremys LAB food supplements should not replace a varied, balanced diet or a healthy lifestyle.
