Effects of Reishi Mushrooms on the Body
Reishi mushrooms (Ganoderma lucidum) demonstrate immunomodulatory, anti-inflammatory, and potential anticancer effects in preclinical studies, but lack high-quality clinical evidence to support therapeutic use in humans beyond serving as a complementary health supplement.
Active Components and Mechanisms
Reishi contains several bioactive compounds that account for its biological effects:
- Polysaccharides (α/β-D-glucans) that modulate immune function and demonstrate anti-inflammatory properties 1
- Triterpenoids including ganoderic acids, ganoderenic acids, and lucidenic acids with potential anticancer activity 1
- Proteins (LZ-8, LZ-9), nucleosides, and nucleotides that contribute to immunomodulation 1
- Sterols and ergosterol with various metabolic effects 1
Documented Biological Effects
Immune System Modulation
- Reishi acts as an immunomodulator, enhancing immune function measures in cancer patients when used as adjuvant therapy 2
- The polysaccharide components demonstrate immunostimulatory effects, though most evidence comes from preclinical studies 2
Anti-Inflammatory Activity
- Flavonoids and polysaccharides suppress pro-inflammatory cytokine release including TNF-α, IL-1β, IL-6, and COX-2 3
- In animal models of rheumatoid arthritis, reishi nanogels significantly reduced inflammatory markers and increased eNOS levels 3
- The anti-inflammatory mechanisms involve prevention of lipid peroxidation due to oxidative stress 3
Anticancer Properties
- Reishi inhibits constitutively active transcription factors NF-κB and AP-1, resulting in suppression of urokinase-type plasminogen activator (uPA) and its receptor uPAR 4
- Demonstrates suppression of cell adhesion and migration in highly invasive breast and prostate cancer cells 4
- When combined with standard cancer therapy, reishi extracts have shown benefits in tumor-related symptoms, performance status, disease-free interval, and overall survival in Asian clinical studies 2
Other Reported Effects
- Potential benefits for hepatic diseases, diabetes, cardiovascular conditions, neurodegeneration, and anxiety based on preclinical evidence 1
- Antioxidative activity through suppression of oxidative stress markers 3
- Traditional use for respiratory infections, hypertension, hyperlipidemia, and gastric ulcers, though clinical validation is limited 5
Critical Clinical Limitations
The most significant caveat is that nearly all pharmacological evidence comes from preclinical studies with substantial methodological drawbacks, and quality clinical data for human use are intensely lacking 1.
Missing Evidence
- No robust clinical trials establishing safety and efficacy for specific medical conditions 1
- Unknown interactions with foods, drinks, and medications 1
- Absent data on chronic use safety, teratogenicity, mutagenicity, and genotoxicity 1
- Variable product quality due to different sources and extraction methods 4
Regulatory Status
- Approved in Japan and China for over 30 years as adjuvant cancer therapy without obvious toxicity 2
- Used primarily as a complementary therapy and health supplement rather than therapeutic agent 5
- No FDA approval for therapeutic indications in the United States 1
Practical Considerations
- Reishi is well-tolerated even in advanced cancer diseases and can be used continuously for long periods 2
- The bitter taste is characteristic of authentic reishi products 5
- Biological activity varies significantly between sources, making it essential to verify product quality 4
- Current evidence supports use only as an immune enhancer and general health supplement, not for specific disease treatment 5
Comparison to Evidence-Based Mushroom Use
Unlike reishi's limited clinical validation, certain mushroom products have established medical applications: