Evidence Level
Beta-Glucans are a class of polysaccharides derived from yeast, fungi, and other sources, known for their immunomodulatory effects. Yeast beta-glucans specifically interact with innate immune cells via Dectin-1 and CR3 receptors, enhancing immune responses (Auinger et al., 2013). A double-blind, randomized controlled trial (RCT) by Auinger et al. (2013) demonstrated that yeast beta-glucan supplementation significantly reduced cold episodes and sick days in healthy individuals.
Recent studies highlight additional benefits of beta-glucans. A systematic review and meta-analysis by Muroya et al. (2025) found that β-glucans significantly reduced fatigue, increased vigor, and improved mood in healthy individuals compared to placebo. Zhong et al. (2021) reported that yeast β-glucans effectively reduced the incidence, duration, and severity of upper respiratory tract infections in healthy subjects.
Vlassopoulou et al. (2021) conducted a systematic review of 34 RCTs involving 917 participants, concluding that fungal beta-glucans improve immune function, reduce respiratory infections, alleviate allergies, enhance mood, and may aid in cancer therapy without adverse effects. These findings underscore the broad potential benefits of beta-glucan supplementation across various populations.
Overall, beta-glucans demonstrate significant immunomodulatory effects supported by multiple clinical studies, making them a valuable supplement for immune health.