1,3 and 1,6 Beta Glucans in Mushrooms: Immune-Boosting Fibers Beyond Digestion

When we think about fiber, most people picture cereal boxes touting “heart-healthy” oats. But not all fibers are created equal—and mushroom beta glucans are in a category of their own. Specifically, 1,3 and 1,6 beta glucans are polysaccharides found in the cell walls of fungi, particularly in functional mushrooms like Lions Mane, oyster, reishi, and turkey tail. These complex carbohydrates are best known for their potent immunomodulating properties (Vetvicka & Vetvickova, 2011).

Unlike soluble fibers from oats that lower cholesterol or insoluble fibers from vegetables that aid motility, mushroom-derived beta glucans do something more nuanced: they actively interact with immune receptors, improving both innate and adaptive responses. These aren't just gut bulk—they're biochemical triggers for wellness.

The Structural Biology of Beta Glucans

Beta Glucans as Soluble Functional Fibers

Beta glucans are glucose polymers linked via beta-glycosidic bonds. The configuration matters: cereal beta glucans are often 1,3/1,4-linked, but mushrooms express 1,3 backbones with 1,6 branches—creating a three-dimensional structure that’s highly biologically active (Brown & Gordon, 2005). These complex structures are recognized by immune cells, unlike simpler plant fibers.

Difference Between 1,3/1,6 Beta Glucans and Other Polysaccharides

What sets mushroom beta glucans apart from chitin (another fungal polysaccharide) or starch is their immunological role. Chitin is mostly structural and indigestible, while starch is purely caloric. Beta glucans functionally bridge immunity and fiber, acting as molecular “keys” for receptor-mediated immune activation (Goodridge et al., 2009). All Polysaccharides are polar compounds, or water soluble, making water extracted processes superior for beta-glucan content, Our Ultrasound Extract is extracted using water as a solvent, allowing the polysaccharides to nano-emulsify for higher bio-availability 

Beta Glucans and the Human Immune System

Dectin-1 Receptors and Innate Immunity Activation

1,3 and 1,6 beta glucans bind to pattern recognition receptors like Dectin-1 on macrophages and dendritic cells. This triggers phagocytosis and cytokine signaling, effectively training the innate immune system to respond faster and stronger to pathogens (Brown, 2006).

Macrophage and NK Cell Response

Beta glucans stimulate macrophage activity and enhance natural killer (NK) cell cytotoxicity. This is especially important for clearing viral-infected cells and early-stage tumor cells, making mushroom beta glucans powerful allies in preventive health (Vetvicka et al., 2013).

Adaptive Immune Regulation via Cytokines

Studies show beta glucans can also upregulate IL-12 and IFN-γ production, bridging innate immunity with adaptive T-helper cell activation (Chan et al., 2009). This dual action is rare among dietary fibers and is part of what makes mushrooms a cornerstone of immunonutrition.

Digestion, Absorption, and the Gut-Lung-Immune Axis

Insoluble vs Soluble Fiber in Fungi

Fungi contain both soluble and insoluble fibers. The insoluble chitin and structural polysaccharides bulk up stool and promote motility. The soluble beta glucans dissolve in the gut, forming a gel-like consistency that resists digestion and reaches the colon where it performs critical immune and microbiome functions (Volman et al., 2008).

Mushroom Beta Glucans as Prebiotics for Gut Flora

Beta glucans act as selective prebiotics—fermented by beneficial bacteria like Bifidobacterium and Lactobacillus. This fermentation increases short-chain fatty acid (SCFA) production such as butyrate, which improves mucosal immunity and reduces systemic inflammation (Roberfroid et al., 2010).

Fermentation Byproducts and SCFA Production

SCFAs serve as fuel for colonocytes and modulate tight junction proteins in the gut lining, supporting barrier integrity. They also communicate with the lungs via the gut-lung axis, making dietary beta glucans a stealthy support for respiratory health as well (Dang & Marsland, 2019).

The Best Mushrooms for Beta Glucans

Oyster Mushrooms (Pleurotus ostreatus)

Oyster mushrooms are among the richest whole-food sources of 1,3/1,6 beta glucans. They’re also inexpensive, widely available, and have a mild flavor that blends easily into various meals. Florida Shroom King’s UMAMI Mushroom Powder offers an easy way to incorporate this functional fiber daily.

Turkey Tail, Reishi, Lions Mane and Oyster

These mushrooms also rank high in beta glucan content, especially when consumed whole or as 1:1 ratio dried powders. Reishi and turkey tail offer complementary immunological effects, while Oyster and Lions Mane mushrooms can be consumed as whole foods or as powders

Why Whole Mushrooms and 1:1 Powders Matter

Highly extracted mushroom products focus on specific compounds like triterpenes or hericenones but often lack the intact beta glucan structure. 1:1 whole-mushroom Lion's Mane powders preserve the original polysaccharide matrix, which is critical for receptor recognition in the body (Zhang et al., 2007).

Eating More Fresh Mushrooms: A Daily Strategy

Mushrooms are one of the most underutilized categories in the produce aisle. From culinary versatility to health benefits, increasing your intake of fresh mushrooms—especially Lions Mane, oyster, shiitake, and maitake—can deliver a steady source of bioavailable beta glucans along with ergothioneine and essential minerals like selenium and potassium (Valverde et al., 2015).

Try sautéing mushrooms with garlic, blending them into soups, or adding 1:1 powders to your morning smoothie. The goal isn’t just diversity—it’s consistency.

 

Summary: Functional Fiber with Immune Precision

Mushroom beta glucans, especially 1,3 and 1,6 linked types, offer more than digestive bulk. They are structurally unique, receptor-activating fibers that modulate immunity, nourish gut bacteria, and support the gut-lung axis. Whether through fresh mushrooms or 1:1 whole-mushroom powders, they are an essential addition to any evidence-based wellness routine.

Q&A: Common Questions About Beta Glucans in Mushrooms

Q1: Are beta glucans from mushrooms different than those in oats or barley?
Yes. Cereal beta glucans are 1,3/1,4-linked and primarily support heart health. Mushroom beta glucans are 1,3/1,6-linked and primarily modulate immune function.

Q2: Can I get enough beta glucans just from supplements?
Not always. Many mushroom extracts remove or degrade beta glucans. Use 1:1 whole mushroom powders or fresh mushrooms for full-spectrum benefits.

Q3: Which mushroom is highest in beta glucans?
Oyster mushrooms have one of the highest concentrations among culinary types. Turkey tail and reishi are top performers among functional varieties.

Q4: How often should I eat mushrooms for beta glucans?
Ideally, include mushrooms in your meals 3–5 times per week, or daily in powder form.

Q5: Do beta glucans survive cooking?
Yes. Beta glucans are heat-stable and remain active after cooking, unlike some volatile antioxidants.

Q6: Are beta glucans safe for everyone?
Generally, yes. Those with autoimmune conditions or on immunosuppressants should consult a healthcare provider first.

References

Brown, G. D., & Gordon, S. (2005). Immune recognition: A new receptor for beta-glucans. Nature, 434(7030), 763–764. https://doi.org/10.1038/434763a

Brown, G. D. (2006). Dectin-1: A signalling non-TLR pattern-recognition receptor. Nature Reviews Immunology, 6(1), 33–43. https://doi.org/10.1038/nri1745

Chan, G. C., Chan, W. K., & Sze, D. M. (2009). The effects of beta-glucan on human immune and cancer cells. Journal of Hematology & Oncology, 2(1), 25. https://doi.org/10.1186/1756-8722-2-25

Dang, A. T., & Marsland, B. J. (2019). Microbes, metabolites, and the gut-lung axis. Mucosal Immunology, 12(4), 843–850. https://doi.org/10.1038/s41385-019-0160-6

Goodridge, H. S., Wolf, A. J., & Underhill, D. M. (2009). Beta-glucan recognition by the innate immune system. Immunological Reviews, 230(1), 38–50. https://doi.org/10.1111/j.1600-065X.2009.00793.x

Jong, S. C., & Birmingham, J. M. (1992). Medicinal benefits of the mushroom Lentinus edodes (Berk.) Sing. International Journal of Medicinal Mushrooms, 1(1), 17–24.

Roberfroid, M., et al. (2010). Prebiotic effects: Metabolic and health benefits. British Journal of Nutrition, 104(S2), S1–S63. https://doi.org/10.1017/S0007114510003363

Valverde, M. E., Hernández-Pérez, T., & Paredes-López, O. (2015). Edible mushrooms: Improving human health and promoting quality life. International Journal of Microbiology, 2015, 376387. https://doi.org/10.1155/2015/376387

Vetvicka, V., & Vetvickova, J. (2011). Physiological effects of different types of beta-glucan. Biomedicine & Pharmacotherapy, 65(6), 437–441. https://doi.org/10.1016/j.biopha.2011.05.012

Vetvicka, V., Vannucci, L., & Sima, P. (2013). The effects of beta-glucan on immune cells. Journal of Clinical & Cellular Immunology, 4(1), 1–8. https://doi.org/10.4172/2155-9899.1000141

Volman, J. J., Ramakers, J. D., & Plat, J. (2008). Dietary modulation of immune function by beta-glucans. Physiology & Behavior, 94(2), 276–284. https://doi.org/10.1016/j.physbeh.2007.11.045

Zhang, M., Cui, S. W., Cheung, P. C. K., & Wang, Q. (2007). Antitumor polysaccharides from mushrooms: A review on their isolation process, structural characteristics and antitumor activity. Trends in Food Science & Technology, 18(1), 4–19. https://doi.org/10.1016/j.tifs.2006.07.013