Ganoderma lucidum and Immune Health: From Ancient Remedy to Clinical Evidence

As we age, the immune system weakens—a process called immunosenescence. The body becomes less effective at fighting infections and responding to vaccines. Both innate immunity (the first line of defense) and adaptive immunity (T and B cells with memory) decline. Older adults produce fewer new T cells, and existing ones work less effectively. At the same time, chronic low-grade inflammation, known as inflammaging, develops. This is driven by inflammatory molecules, such as IL-6, TNF-α, and IL-1β, and is associated with diseases like heart disease, dementia, and cancer.

    T cells also communicate less effectively with age. Helpful signals, such as the decline of IL-2, while pro-inflammatory cells like Th17 become more active. Normally, regulatory T cells (Tregs) release calming signals, such as IL-10, IL-35, and TGF-β; however, these protective factors are diminished in older adults, contributing to higher risks of cardiovascular disease and diabetes.

    Ganoderma lucidum (Reishi, also known as Ling Zhi) has been used in traditional Chinese medicine for over 2,000 years. Modern research shows it strengthens the immune system by stimulating T cells, B cells, natural killer (NK) cells, and dendritic cells. Its main active compounds are polysaccharides, especially β-glucans, which help immune cells communicate and release cytokines. Another compound, Ling Zhi-8 protein, enhances IL-2 production, which is crucial for maintaining an aging immune system.

    Clinical studies support these effects. In one trial, 39 older women took 2,000 mg of Ganoderma extract per day for 8 weeks. Compared to the placebo, they showed an improved immune balance, characterized by lower inflammatory Th17 cells and higher protective Th2 cells, with increased anti-inflammatory activity.

    In another study, 34 advanced cancer patients received Ganopoly (1,800 mg, three times daily, totaling 5,400 mg/day) for 12 weeks. Since each capsule contained 600 mg of extract with 25% polysaccharides, this dose equaled approximately 270 g of raw mushroom daily—similar to traditional Chinese medicine doses of 50–300 g per day. Results showed increases in IL-2, IL-6, and interferon-gamma, while IL-1 and TNF-α decreased. NK cell numbers rose significantly, and their activity improved from 26.6% to 34.5%. T cells (CD3, CD4, and CD8) rose slightly, although the CD4:CD8 ratio remained stable. These findings suggest Ganopoly helps restore immune defenses in cancer patients.

    Because cancer progression depends on both tumor aggressiveness and immune strength, boosting NK and T cell activity is crucial. Standard treatments, such as chemotherapy and radiation, often suppress the immune system, but combining them with immune-modulating agents, like Ganopoly, may improve outcomes. Importantly, Ganopoly may also reduce TNF-α, a key driver of cancer cachexia (characterized by weight loss, fatigue, and poor sleep), potentially improving quality of life.

    A larger clinical study in 120 breast and lung cancer patients after surgery tested G. lucidum spore powder (2,000 mg twice daily for 6 weeks). Patients taking Reishi had higher levels of helpful T cells (CD3+CD4+, CD3+HLADR−; p < 0.05), and lower levels of suppressive T cells (CD4+CD25+ Treg, CD3+HLADR+; p < 0.05). IL-12 rose significantly, while IL-10, COX2, and TGF-β1 fell (p < 0.05).

    The albumin-to-globulin ratio (AGR) and neutrophil-to-lymphocyte ratio (NLR) are common blood markers. They reflect the body’s nutritional status and level of inflammation, and in cancer patients, they are often used to predict immune function and survival outcomes. Survival analysis revealed that patients with high AGR (≥1.5) and low NLR (≤2.5) experienced the best progression-free and overall survival rates, whereas a low AGR/high NLR ratio predicted poorer outcomes.

    Taken together, these studies suggest that Ganoderma lucidum (Reishi mushroom) helps strengthen immunity by boosting T cells, NK cells, and anti-inflammatory signals while lowering harmful inflammation. Clinical studies have shown that daily use improves immune balance in older adults and cancer patients, with some evidence suggesting better survival and quality of life.

References:

1.         Iser-Bem PN, Lobato TB, Alecrim-Zeza AL, Dos Santos de Oliveira LC, Passos MEP, Manuel R, Diniz VLS, Correa IS, de Oliveira SP, Silva EBD, Almeida MM, Dias BB, Gritte RB, Levada-Pires AC, Masi LN, Hatanaka E, Pithon-Curi TC, Hirabara SM, Fabi JP, Curi R, Gorjao R. Ganoderma lucidum dry extract supplementation modulates T lymphocyte function in older women. Br J Nutr. 2024 Jul 28;132(2):130-140. doi: 10.1017/S0007114524001144. Epub 2024 May 27. PMID: 38800991.

2.         Gao Y, Zhou S, Jiang W, Huang M, Dai X. Effects of ganopoly (a Ganoderma lucidum polysaccharide extract) on the immune functions in advanced-stage cancer patients. Immunol Invest. 2003 Aug;32(3):201-15. doi: 10.1081/imm-120022979. PMID: 12916709.

3.         Deng Y, Ma J, Tang D, Zhang Q. Dynamic biomarkers indicate the immunological benefits provided by Ganoderma spore powder in post-operative breast and lung cancer patients. Clin Transl Oncol. 2021 Jul;23(7):1481-1490. doi: 10.1007/s12094-020-02547-9. Epub 2021 Jan 6. PMID: 33405051.

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