Yeast Beta-Glucan

Yeast beta-glucan is a type of soluble fiber derived from the cell walls of Saccharomyces cerevisiae (baker’s yeast). It is best known for its ability to modulate the immune system.

Unlike fiber from grains, which primarily supports digestion, yeast beta-glucans bind to immune cells and stimulate their activity, helping the body respond more efficiently to stress and infection. This has made it a valuable ingredient in immune-support supplements, especially for athletes under intense training who may experience temporary immune suppression.

In physically active individuals, yeast beta-glucan can help reduce the risk of upper respiratory tract infections (URTIs), which are common after prolonged or strenuous exercise. It works by activating macrophages and natural killer cells — components of the innate immune system — without overstimulating the immune response.

It is considered safe and well-tolerated, with a growing body of scientific literature supporting its benefits in enhancing immune readiness and reducing sick days among athletes and military personnel.

Synonyms:

Beta-1,3/1,6-glucan, Immune yeast extract.

Benefits:

  • Supports a healthy immune response during and after intense exercise
  • May reduce the incidence and duration of exercise-induced URTIs
  • Helps maintain overall immune vigilance without overstimulation

Sources:

Extracted from the cell walls of Saccharomyces cerevisiae (baker’s yeast).

Observations:

Found in capsule or powder form, often combined with vitamins and minerals in immune-support blends. Typical dosages range from 250 mg to 500 mg per day.

Usually well-tolerated, but high doses may cause mild gastrointestinal effects in sensitive individuals. Does not provide the same cholesterol-lowering benefits as beta-glucans from oats or barley.

Areas of Study:

Immunology, Sports Science, Nutritional Biochemistry, Clinical Nutrition.