Beta-glucan is a long-chain polysaccharide (consisting only of D-glucose chains) linked together by specific beta-1,3-glycosidic bonds, and in some places, it also contains side beta-1,6-glycosidic bonds that allow branching of polymer molecules. It has an incredible property of activating the immune system. This 1,3/1,6 linkage is crucial because other forms do not affect immunity but rather regulate cholesterol and blood sugar. Beta-glucan activates key immune system cells in the body – phagocytes, macrophages, neutrophils, eosinophils, and NK cells (natural killer cells), enabling them to act more quickly in recognizing and destroying harmful pathogenic microorganisms to which we are exposed daily. It has been shown that beta-glucan increases immune activity by 50-120% in the first 72 hours after ingestion.