Beta-glucans are sugars that are found in the cell walls of bacteria, fungi, yeasts, algae, lichens, and plants, such as oats and barley. At dietary intake levels of at least 3 g per day, oat fiber, β-glucan decreases blood levels of LDL cholesterol and so may reduce the risk of cardiovascular diseases. 

β-glucans are used as texturing agents in various nutraceutical and cosmetic products, and as soluble fiber supplements. Beta-glucan is also purported to help the body fend off colds, the flu, and even cancer, as well as increase defenses against the harmful effects of stress