Mushroom

    Shiitake

    Lentinula edodes

    TL;DR

    Shiitake's injectable beta-glucan has real oncology data in Japan; the oral supplement mostly shows immune-marker shifts, not proven clinical benefit.

    Ideal For

    • People wanting a food-first immune and gut-microbiome support
    • Those seeking a nutrient-dense culinary mushroom

    Avoid If

    • You have a mushroom allergy
    • You have an eosinophilic disorder

    Frequently Asked Questions

    What is shiitake used for?
    Beyond cooking, it is taken for immune support. Its beta-glucan lentinan is used as an injectable oncology adjuvant in Japan - a very different context from oral capsules.
    Does oral shiitake do anything?
    Small human studies show changes in immune markers such as secretory IgA and cytokine profiles. Whether that translates to fewer infections is unproven.
    Does it affect cholesterol?
    Eritadenine in shiitake modestly lowered cholesterol in animal work; human data is sparse and unconvincing.
    What dose is used?
    Studies have used 5-10 g/day of dried mushroom, or extracts standardised to beta-glucan content. Culinary amounts are a reasonable starting point.
    Is it safe?
    Yes as food. Raw or undercooked shiitake can cause shiitake dermatitis - a striking whip-like rash - which is why it should be cooked thoroughly.
    Who should be careful?
    People on immunosuppressants, since immune-modulating effects are theoretically unhelpful there. Mushroom allergy also applies.

    Overview

    Lentinan, a purified beta-1,3-glucan from Lentinula edodes, is approved in Japan as an intravenous adjuvant to chemotherapy in gastric cancer, where meta-analyses of Japanese trials report modest survival gains. That evidence does not transfer to oral capsules: swallowed beta-glucans are not absorbed intact and act on gut-associated lymphoid tissue instead. Small human studies of daily shiitake consumption report increased secretory IgA, altered cytokine profiles, and improved gut bacterial diversity — biologically interesting, but not tied to fewer infections or other hard endpoints. Eritadenine, a purine alkaloid unique to shiitake, lowers cholesterol in animals through altered phospholipid metabolism, with only weak human confirmation. A distinctive adverse effect is shiitake dermatitis, a flagellate rash caused by lentinan in raw or undercooked mushrooms, which resolves with cooking. Shiitake is a nutritious food with plausible immune effects; the supplement industry's claims run well ahead of the trials.

    How It Works

    • Beta-1,3/1,6-glucans bind dectin-1 receptors on gut immune cells
    • Lentinan stimulates T-helper and NK cell activity in preclinical models
    • Eritadenine alters hepatic phospholipid metabolism, lowering cholesterol in animals
    • Prebiotic fiber content supports short-chain fatty acid production

    Health Concerns Addressed

    No linked health concerns yet.

    Supporting Research
    5 studies

    Consuming Lentinula edodes (Shiitake) Mushrooms Daily Improves Human Immunity: A Randomized Dietary Intervention in Healthy Young Adults

    Score: 6/10
    2015
    rct
    n=52

    Dai X, Stanilka JM, Rowe CA +6 more

    Four weeks of daily shiitake consumption increased gamma delta T-cell proliferation and secretory IgA while reducing C-reactive protein in healthy young adults.

    View source

    Modulation of human intestinal microbiota in a clinical trial by consumption of a beta-D-glucan-enriched extract obtained from Lentinula edodes

    Score: 6/10
    2021
    rct
    0

    Morales D, Shetty SA, Lopez-Plaza B +4 more

    A shiitake beta-glucan extract shifted gut microbiota composition and short-chain fatty acid producers in hyperlipidaemic adults without major lipid changes.

    View source

    Lentinula edodes mycelia extract plus adjuvant chemotherapy for breast cancer patients: results of a randomized study on host quality of life and immune function improvement

    Score: 4/10
    2017
    rct
    0

    Suzuki N, Takimoto Y, Suzuki R +5 more

    Lentinula edodes mycelia extract alongside adjuvant chemotherapy improved quality of life scores and some immune parameters.

    View source

    Evaluation of host quality of life and immune function in breast cancer patients treated with adjuvant chemotherapy plus oral administration of Lentinula edodes mycelia extract

    Score: 4/10
    2013
    rct
    0

    Nagashima Y, Maeda N, Yamamoto S +2 more

    Patients receiving the mycelia extract reported less chemotherapy-related fatigue and maintained natural killer cell activity better than controls.

    View source

    Beta-glucans in higher fungi and their health effects

    Score: 4/10
    2009
    systematic_review
    0

    Rop O, Mlcek J, Jurikova T

    Fungal beta-glucans including lentinan from shiitake show immunomodulatory and cholesterol-lowering activity in experimental and early clinical work.

    View source

    Safety Information

    Potential Side Effects

    {"Shiitake dermatitis (flagellate rash) from raw mushrooms; bloating; eosinophilia at high doses"}

    Contraindications

    {"Mushroom allergy"}

    Drug Interactions

    • Possible additive effects with immunosuppressants
    • Theoretical interaction with anticoagulants

    Pregnancy & Breastfeeding

    Pregnancy: Likely safe

    Breastfeeding: Likely safe

    Dosage Guidelines

    Dosage Used in Studies

    Consult healthcare provider

    Dosing by Goal

    GoalDoseNotes
    General1-3g/day of extract, or 5-10g dried mushroom daily as food.

    Forms Compared

    Whole dried mushroom/powder

    Closest to the food-based evidence

    Hot-water beta-glucan extract

    Concentrates the polysaccharide fraction

    Lentinan injection

    Prescription-only oncology adjuvant in Japan, not a supplement

    Food & Timing

    With meals; cooking prevents shiitake dermatitis.

    Medical Disclaimer

    The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.

    Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.