Sources of Beta Glucan

Beta glucans are naturally occurring sugar molecules, also known as polysaccharides, that have been widely touted as a powerful stimulant for the human immune system. This form of fiber, which can be found in a wide variety of plant material, has also been promoted as a natural way to reduce cholesterol and blood glucose levels. Because of the many ways in which beta glucans are reputed to help bolster human health, these simple polysaccharides have been getting a lot of attention in recent years.

Fighting Infection

• The website of the Beta Glucan Research Organization (BGRO) offers extensive information about research into the substance's immune-enhancing powers, observing that "beta glucan is a scientifically proven biological defense modifier (BDM) that nutritionally potentiates and modulates the immune response." It does this by stimulating the body's white blood cells---those that fight both viral and bacterial infection---into action, thus maximizing the immunoresponse to the threat of infection.

Quality, Not Quantity

• In assessing differing levels of beta glucan effectiveness, BGRO contends that the efficacy of any given beta glucan supplement depends less on the quantity of beta glucans contained therein than it does on the source from which the substance was obtained. BGRO says that important factors other than source include "processing (including avoidance of reaggregation during digestion), sizing and uniformity of beta glucan particles ingested."

Natural Sources

• Beta glucans can be found in many natural materials, and the specific properties of a beta glucan supplement seem to vary depending on the source. Four of the most common sources for beta glucans are yeast, barley, mushrooms and oats.

Yeast and Barley

• Beta glucans derived from yeast seem to be particularly effective in stimulating the immune system and also in their ability to reduce blood cholesterol levels. This makes yeast-derived beta glucan supplements widely recommended for use in the treatment of tumors or radiation injury. Research has shown, however, that barley-derived beta glucans offer less stimulus to the immune system but are particularly effective in reducing levels of both blood glucose and cholesterol (both total cholesterol and the so-called bad cholesterol).

Mushroom and Oats

• Beta glucans sourced from mushrooms show some promise as a supplement for patients who are fighting colon cancer, although research indicates they are less effective in stimulating the immune system than yeast-derived beta glucans. The effectiveness of mushroom-derived beta glucans seems also to vary based on the specific species of mushroom from which they were extracted. Research on beta glucans from oats indicates that their greatest strengths lie in their ability to reduce levels of blood cholesterol and blood glucose.

What Lies Ahead?

• The healing properties of beta glucans continue to be studied, both in the United States and abroad. In Japan, various strains of mushroom-derived beta glucans have been used for more than two decades as a companion therapy to chemotherapy in cancer patients. Trials are underway in the United States for comparable use of beta glucan therapy but have not yet won approval from the U.S. Food and Drug Administration.