Key Takeaways
- Immune-Boosting Compounds: Functional mushrooms like Reishi, Shiitake, Maitake, Oyster Mushroom, and Turkey Tail contain bioactive compounds like beta-glucans that interact with immune receptors to enhance responses against winter viruses, potentially reducing infection incidence by 25–60% based on some clinical studies.
- Specific Benefits by Mushroom: Oyster mushroom (pleuran) significantly cuts recurrent respiratory infections in children; Reishi improves NK cell activity; Shiitake (AHCC) aids viral clearance; Maitake boosts flu vaccine effectiveness; and Turkey Tail offers antiviral properties through PSP and PSK.
- Trained Immunity Mechanism: These mushrooms induce "trained immunity," a long-lasting (3–12 months) non-specific immune memory via metabolic and epigenetic changes, providing broad protection against colds, flu, and sore throats.
- Dosage and Administration Insights: Effective doses range from 250mg to 3–7g daily (adults); liquid forms may offer better absorption (up to x12.5 according to some studies), with once to two daily intake recommended (morning and evening) for optimal results.
- Safety and Practical Use: Studies show low side effects (under 5%, mostly mild); ideal for at-risk groups like children, seniors, and athletes, but consult a doctor, especially with allergies or conditions, and combine with lifestyle habits for winter wellness.
Functional Mushrooms and Winter Illnesses: Exploring Their Role in Prevention and Treatment of Colds, Flu, and Sore Throats
With winter comes the familiar wave of sniffles, coughs, and fatigue from common illnesses like colds, flu, and sore throats. These respiratory infections, often triggered by viruses or bacteria, affect millions each year, disrupting work, school, and daily routines. While vaccines and good hygiene remain essential, emerging research highlights functional mushrooms as natural allies for immune support. Mushrooms such as oyster (Pleurotus ostreatus), Reishi (Ganoderma lucidum), Shiitake (Lentinula edodes), Maitake (Grifola frondosa), and Turkey Tail (Trametes versicolor) contain compounds that may help the body fend off these seasonal threats.
This post draws from recent scientific studies to explain how these mushrooms work, their studied benefits, and practical insights. Whether you're a busy professional seeking stress relief or an older adult focused on healthy aging, this overview aims to educate on science-backed options for immune health.
The Basics of Functional Mushrooms and Their Role in Fighting Winter Illnesses
Functional mushrooms are types with health-promoting properties beyond basic nutrition. They contain bioactive compounds in their cell that interact with our immune system to help detect and respond to threats like viruses. Research has explored their use in preventing or easing respiratory infections, including the common cold (caused by rhinoviruses), flu (influenza viruses), and upper airway issues like sore throats. Here's a breakdown of the key mushrooms, supported by clinical studies.
Spotlight on Key Mushrooms and What Studies Show
Reishi (Ganoderma lucidum)
This mushroom's polysaccharides act as immune boosters. A controlled trial with 83 healthy adults tested 250 mg of Reishi beta-glucan daily, showing improved activity of natural killer (NK) cells, which help fight infections (Evaluation of immune modulation..., 2023). Lab tests combined Reishi with Echinacea to block flu viruses A and B (Ma et al., 2024). In animal studies, it reduced lung inflammation from bacterial-like triggers by calming overactive immune responses and protecting lung cells (Lee et al., 2022; Tang et al., 2022).
Oyster Mushroom (Pleurotus ostreatus)
Known for its beta-glucan called pleuran, this mushroom has been tested mainly in children to prevent repeated respiratory infections. In a large study across seven European countries with 1,030 kids (average age about 3.5 years), a liquid form of pleuran (combined with vitamin C) was given daily for three months at a dose based on body weight. Compared to the previous year, infections dropped by 45%, including ear infections (down 58%), sore throats (down 52%), and colds (down 25%). The total days sick also fell by nearly half, with very few side effects—just five mild ones among all participants (Rennerova et al., 2022).Another study looked at herpes simplex virus (related to some respiratory symptoms), using higher doses during active infection and lower for prevention. It shortened symptoms and made them less severe (Jesenak et al., 2020).
Shiitake (Lentinula edodes) and AHCC
Shiitake's lentinan and AHCC (a special extract from grown mycelium) target ongoing viral issues. A mid-stage trial gave 3 grams of AHCC daily for six months to 22 people with persistent HPV infections (a virus model relevant to respiratory ones). It cleared the virus in about 64% of cases, boosted immune signals like interferons, and enhanced NK and T-cell function without notable side effects (Smith et al., 2022). In lung cell experiments, Shiitake beta-glucans lowered inflammation markers and oxidative stress, which could help with conditions like severe colds or flu (Murphy et al., 2020). Lentinan balances immune activation by curbing excess inflammation while ramping up protective responses (Ahn et al., 2017).
Maitake (Grifola frondosa)
Maitake stands out for improving how the body responds to flu vaccines. In a placebo-controlled study of 100 adults, 6.825 grams daily for 12 weeks (starting before vaccination) raised antibody levels against flu strains, especially in those over 60. It also eased cold symptoms like runny noses and headaches, improving overall well-being (Dicks et al., 2017).
Turkey Tail (Trametes versicolor)
Its compounds PSP and PSK have antiviral effects. Lab studies show PSP slows virus copying, boosts antiviral chemicals, and activates immune pathways to produce protective proteins and cells (Rodríguez-Valentín et al., 2018). PSK works similarly, encouraging a strong immune alert through specific receptors (Lu et al., 2011).
How They Work: Simple Science Behind the Benefits
Bioactive compounds like Beta-glucans "train" the immune system by binding to receptors on cells like macrophages and NK cells, sparking signals that produce helpful proteins (cytokines) for fighting invaders (Han et al., 2020). This includes an exciting process called "trained immunity," where the body remembers past exposures, not like a vaccine for one germ, but a general boost lasting months. It involves changes in cell energy use and gene activity, making responses quicker and stronger against various threats (Netea et al., 2016; Horneck Johnston et al., 2024).
Forms, Doses, and How to Take Them
Evidence shows that liquid extracts might absorb better than powders. One Reishi study found that liquids offered better bioavailability, with 12.5-fold higher solubility and increased blood/lung exposure (Wang et al., 2017). Doses from studies include:
|
Mushroom/Compound
|
Population
|
Dosage
|
Duration
|
Key Outcomes
|
|
Pleuran (Pleurotus)
|
Children (1–12 yrs)
|
10 mg/5 kg body wt daily
|
3 months
|
45.3% fewer infections (Rennerova et al., 2022)
|
|
Beta-glucan (Reishi)
|
Adults
|
250 mg daily
|
Variable
|
↑
Better NK cell function
(Evaluation..., 2023)
|
|
AHCC (Shiitake)
|
Adults
|
3 g daily
|
6 months
|
Virus clearance in
63.6% (Smith et al., 2022)
|
|
Maitake
|
Adults (>60 yrs)
|
6.825 g daily
|
12 weeks
|
Stronger vaccine response, fewer cold symptoms
(Dicks et al., 2017)
|
|
Yeast beta-glucans (comparative)
|
Adults (athletes)
|
250–500 mg daily
|
4–12 weeks
|
Fewer sick days after exercise
(Mah et al., 2020; Carpenter et al., 2013) |
Most studies recommend once to two daily intake, ideally in the morning & evening on an empty stomach, for steady effects (Zhong et al., 2021).
Implications of the Research for Immune Health and Winter Wellness
These findings suggest functional mushrooms could help cut down winter illnesses by 25–60% in certain groups, based on infection rates, symptom length, and severity in trials (Jesenak et al., 2017; Vetvicka et al., 2013). This is important because seasonal bugs lead to widespread discomfort and economic costs, like missed work.
For families with kids prone to repeated colds, common in daycare or school settings, oyster mushroom's results offer hope for fewer doctor visits.
In older adults and aging populations (60 years old and plus), where immune strength naturally dips, Maitake's vaccine boost could mean better protection from flu complications (Dicks et al., 2017). Reishi and Shiitake's anti-inflammatory actions might ease the body's overreaction to viruses, reducing issues like persistent coughs (Lee et al., 2022; Murphy et al., 2020).
The "trained immunity" idea is a game-changer: It provides broad defense, not just against one virus, helping fill gaps when new strains emerge (Collins et al., 2020).
Reviews confirm beta-glucans often lessen symptom intensity, though not always prevent every case (Zhong et al., 2021; Auinger et al., 2013).
Safety is a plus: side effects are rare and mild, like minor stomach upset, unlike some meds that can build resistance (Bergendiova et al., 2011).
For active 30–50-year-olds, this could counter post-workout slumps that invite colds (Mah et al., 2020; Bobovcak et al., 2010).
Seniors might appreciate the support for vitality without heavy reliance on pills.
While not a cure-all, these mushrooms complement basics like handwashing, adding a natural layer to winter prep.
Practical Tips and Looking Ahead
- If you're considering functional mushrooms for immune support, talk to a doctor first, especially if you have allergies to mushrooms, autoimmune issues, or take immunosuppressants.
- Opt for concentrated liquids forms in order to benefit from the improved bioavailability.
- For prevention, begin 4–6 weeks before cold season peaks, aiming for 3–6 months to build that trained effect (Netea et al., 2016). Pair with vitamins like C or D for possible extra benefits.
- Track your own experience, like fewer sick days, to see what works.
- Choose based on needs: Oyster for kids' prevention, Maitake around flu shots, Reishi or Shiitake for everyday immune tune-ups. Combine with healthy habits: balanced meals, exercise, rest... for best results.
References
- Ahn, H., Jeon, E. J., Kim, J. C., et al. (2017). Lentinan from shiitake selectively attenuates AIM2 and non-canonical inflammasome activation while inducing pro-inflammatory cytokine production. Scientific Reports, 7(1), 1314. https://doi.org/10.1038/s41598-017-01592-z
- Auinger, A., Riede, L., Bothe, G., Busch, R., & Gruenwald, J. (2013). Yeast (1,3)-(1,6)-beta-glucan helps to maintain the body's defence against pathogens: A double-blind, randomized, placebo-controlled, multicentric study in healthy subjects. European Journal of Nutrition, 52(8), 1913-1918. https://doi.org/10.1007/s00394-013-0492-z
- Benson, K. F., Stamets, P., Davis, R., et al. (2019). The effect of AHCC® on NK and T cells: A review on human and animal studies. Journal of Immunology Research, 2019, 3758576. https://doi.org/10.1155/2019/3758576
- Bergendiova, K., Tibenska, E., & Majtan, J. (2011). Pleuran (β-glucan from Pleurotus ostreatus) supplementation, cellular immune response and respiratory tract infections in athletes. European Journal of Applied Physiology, 111(9), 2033-2040. https://doi.org/10.1007/s00421-011-1837-z
- Bobovcak, M., Kuniakova, R., Gabriz, J., & Majtan, J. (2010). Effect of pleuran (β-glucan from Pleurotus ostreatus) supplementation on cellular immune response after intensive exercise in elite athletes. Applied Physiology, Nutrition, and Metabolism, 35(6), 755-762. https://doi.org/10.1139/H10-070
- Carpenter, K. C., Breslin, W. L., Davidson, T., Adams, A., & McFarlin, B. K. (2013). Baker's yeast beta-glucan supplementation increases salivary IgA and decreases cold/flu symptomatic days after intense exercise. Journal of Dietary Supplements, 10(3), 171-183. https://doi.org/10.3109/19390211.2013.820248
- Collins, A., Miles, E. A., & Calder, P. C. (2020). Could the induction of trained immunity by β-glucan serve as a defense against COVID-19? Frontiers in Immunology, 11, 1782. https://doi.org/10.3389/fimmu.2020.01782
- Dicks, L., Kirsten, W., & Swanevelder, S. (2017). Maitake mushrooms (Grifola frondosa) enhances antibody production in response to influenza vaccination in healthy adult volunteers concurrent with alleviation of common cold symptoms. Functional Foods in Health and Disease, 7(7), 386-398. https://doi.org/10.31989/ffhd.v7i7.363
- Evaluation of immune modulation by β-1,3; 1,6 D-glucan derived from Ganoderma lucidum in healthy adult volunteers: A randomized controlled trial. (2023). Foods, 12(3), 659. https://doi.org/10.3390/foods12030659
- Han, B., Baruah, K., Cox, E., Vanrompay, D., & Bossier, P. (2020). Structure-functional activity relationship of β-glucans from the perspective of immunomodulation: A mini-review. Frontiers in Immunology, 11, 658. https://doi.org/10.3389/fimmu.2020.00658
- Horneck Johnston, C. J. H., Ledwith, A. E., Byrne, R. M., et al. (2024). Recognition of yeast β-glucan particles triggers immunometabolic signaling required for trained immunity. iScience, 27(3), 109030. https://doi.org/10.1016/j.isci.2024.109030
- Jesenak, M., Majtan, J., Rennerova, Z., et al. (2013). Immunomodulatory effect of pleuran (β-glucan from Pleurotus ostreatus) in children with recurrent respiratory tract infections. International Immunopharmacology, 15(2), 395-399. https://doi.org/10.1016/j.intimp.2012.11.020
- Jesenak, M., Sanislo, L., Kuniakova, R., et al. (2020). Efficacy of Pleuran (β-glucan from Pleurotus ostreatus) in the Management of Herpes Simplex Virus Type 1 Infection. Evidence-Based Complementary and Alternative Medicine, 2020, 8562309. https://doi.org/10.1155/2020/8562309
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- Mah, E., Kaden, V. N., Kelley, K. M., & Liska, D. J. (2020). Beverage containing dispersible yeast β-glucan decreases cold/flu symptomatic days after intense exercise: A randomized controlled trial. Journal of Dietary Supplements, 17(2), 200-210. https://doi.org/10.1080/19390211.2018.1495676
- Murphy, E. J., Masterson, C., Rezoagli, E., et al. (2020). β-Glucan extracts from the same edible shiitake mushroom Lentinus edodes produce differential in-vitro immunomodulatory and pulmonary cytoprotective effects—Implications for coronavirus disease (COVID-19) immunotherapies. Science of the Total Environment, 732, 139330. https://doi.org/10.1016/j.scitotenv.2020.139330
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