Beta-glucan

Figure 1. Oatmeal is a common source of Beta-glucans.

Beta-glucans comprise a group of Beta-D-glucose polysaccharides (glucans) naturally occurring in the cell walls of cereals, bacteria, and fungi. They are soluble dietary fibers that are readily available from oat and barley grains and possess multiple functional and bioactive properties, including applications in insulin resistance, dyslipidemia, hypertension, and obesity.

The fermentability of Beta-glucans and their ability to form highly viscous solutions in the human gut have widened the applicability of Beta-glucan as a food ingredient with the dual purposes of increasing the fiber content of food products and enhancing their health properties.

Like other types of soluble fiber, Beta-glucan slows the passage of food as it travels through your intestines. This increases the time it takes for your body to digest food, which keeps you feeling full longer, which is an important aspect of dietary management.

Beta-glucan also slows the absorption of sugar into your bloodstream. This can help stabilize blood sugar levels and improve blood sugar regulation.

Food Sources

One of the most common sources of Beta(1,3)D-glucan for supplement use is derived from the cell wall of baker's yeast (i.e. Saccharomyces cerevisiae). Other sources include seaweed and various mushrooms such as lingzhi, shiitake, chaga, and maitake. In addition, Beta-glucan is commonly found in:

• Oats
• Barley
• Sorghum
• Rye
• Maize
• Triticale
• Wheat
• Durum Wheat
• Rice

Taken as a Dietary Supplement

A dietary intake of at least 3g per day of Beta-glucan for 8 weeks may decrease blood levels of LDL cholesterol, thus reducing the risk of cardiovascular diseases and improving heart health. Studies have shown that with an intake of at least 3g per day, Beta-glucan lowers total and low-density lipoprotein cholesterol levels by 5 to 10% in people with normal or elevated blood cholesterol levels. As such, it has been linked to other potential health benefits such as decreasing inflammation and improving blood sugar management. 

Beta-glucans are a source of soluble, fermentable fiber--also called prebiotic fiber--which provides a substrate for microbiota within the large intestine. This has the effect of increasing fecal bulk and producing short-chain fatty acids as by-products. This fermentation process affects digestive function and cholesterol and glucose metabolism, as well as the immune system and other systemic functions within the human body. More specifically, Beta-glucan has been shown to increase the activity of certain types of immune cells, including macrophages, neutrophils, and monocytes.