Beta-Glucans

Beta-glucan · Oat beta-glucan · Yeast beta-glucan

Snapshot

Indications	Contraindications
Cholesterol lowering^{1, 2} Postprandial glucose^{3, 4} Respiratory infection frequency^{5, 6} Influenza vaccine antibody response⁷ Asthma control in children⁶ Adjunct during cancer therapy⁵ Body weight⁸	Autoimmune disorders⁹ Immunosuppressant therapy⁹

Beta-glucans are soluble glucose polysaccharides from oats, barley, yeast, mushrooms, and algae, and their source determines their behavior^{10, 11}. Cereal forms act as viscous fiber in the gut, while yeast and fungal forms engage innate immune cells. Supplementation is used for cholesterol and postprandial glucose, and for immune support, including respiratory infection frequency and antibody response to influenza vaccination⁵. Typical patients are adults with raised cholesterol, people with recurrent respiratory infections, and older adults receiving seasonal vaccines.

Meta-analyses of randomized trials found oat beta-glucan lowered low-density lipoprotein (LDL) cholesterol, and one found isolated beta-glucan supplements also lowered LDL^{1, 2}. For fungal beta-glucans, a systematic review of randomized trials reported fewer respiratory infections and milder symptoms, though cellular immune findings were inconsistent. In mice, a 2026 study found dietary yeast beta-glucan reprogrammed blood-forming progenitor cells and restored anti-tumor immunity in obesity; no human trial has tested it. Over two thousand products list beta-glucans, mostly as capsules from yeast, mushroom, or cereal sources; see Form comparison.

United States product labels ask for consultation with a health professional before use in autoimmune disorders, after organ transplant, or with immunosuppressants⁹. Health Canada lists a barley content statement on some licensed single-ingredient products¹².

Last updated October 16, 2026. Read how we make monographs.

In the full monograph

68 sources, 58 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Snapshot

In the full monograph

Sources