What Is Beta-Glucan?

Beta-Glucan tablets, capsules, oats, barley, and wheat

Verywell / Anastasia Tretiak

Beta-glucan is a soluble fiber found naturally in cereal grains, yeast, and certain mushrooms and sold as a supplement. A polysaccharide—a large molecule made up of multiple sugar molecules—beta-glucan may offer a number of health benefits, including lowering cholesterol, improving blood sugar management, and boosting the immune system.

What Is Beta-Glucan Used For?

As a soluble fiber, beta-glucan itself is not digested, but it does slow food transit in the intestines. As a result, carbohydrates are absorbed slower, resulting in more steady blood sugar. In addition, it moves slowly through the digestive tract, taking cholesterol with it as it goes.

In addition to the benefits this can have for diabetes and high cholesterol, alternative medicine proponents claim that beta-glucan supplements may help with the following health conditions:

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.

So far, however, scientific support for the benefits of beta-glucan is limited. If you're considering using beta-glucan supplements, talk to your healthcare provider to weigh the potential risks and benefits.

Keep in mind that alternative medicine should not be used as a substitute for standard care. Self-treating a condition and avoiding or delaying standard care may have serious consequences.

Here's a look at some key study findings on the possible health benefits of beta-glucan.

Cholesterol

The beta-glucan found in oats may help keep cholesterol in check, according to a 2011 report. Looking at studies conducted over the previous 13 years, the report's authors determined that oat-derived beta-glucan may significantly reduce levels of total and LDL ("bad") cholesterol. The authors noted that, on average, daily oat consumption is associated with 5% and 7% reductions in total and LDL cholesterol levels, respectively.

A 2014 meta-analysis found similar results. The researchers focused on studies that included at least 3 grams (g) of beta-glucan daily and found it reduced total cholesterol and LDL cholesterol, but did not impact HDL cholesterol levels or triglycerides.

Diabetes

Research also suggests that beta-glucan may help manage diabetes by controlling blood sugar levels, lowering cholesterol, and keeping blood pressure in check.

A 2014 literature analysis confirmed these findings but noted that beta-glucan alone was not enough to achieve normal blood sugar readings in patients with diabetes, and it should be used as an adjunct to standard treatment.

Cancer

Preliminary research indicates that beta-glucan may activate a number of cells and proteins that fight cancer (such as T-cells and natural killer cells). What's more, tests on animals have shown that beta-glucan may inhibit the spread of cancer cells.

However, a 2009 report cautions that there are "no good quality clinical trial data" for the effectiveness of beta-glucan in treating cancer.

Immunity

Currently, there is a lack of clinical trials supporting the claim that beta-glucan can "rev up" the immune system and stave off colds, flu, and other types of infection.

Possible Side Effects

Although beta-glucan is generally considered safe, there's some concern that it may lower blood sugar. While a benefit in some cases, this can be dangerous in others. People with hypoglycemia or anyone taking medications to reduce blood sugar should consult a healthcare provider before using beta-glucan.

People who eat a low-fiber diet should start with a lower dose of beta-glucan and increase it gradually. Like all sources of fiber, it may cause gastric distress, bloating, and gas if taken in larger-than-normal doses. The side effects should wear off over time, but slowly introducing it can help you avoid this.

Supplements haven't been tested for safety. And since dietary supplements are largely unregulated, the content of some products may differ from what is specified on their product labels.

Also keep in mind that the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established.

Dosage and Preparation

Oats, barley, and wheat
Verywell / Anastasia Tretiak

There is no standard dose for beta-glucan. Research has shown various levels to be effective, and the amount needed differs based on the source.

For instance, beta-glucans from yeast may lower cholesterol at 7.5 grams taken twice daily for seven to eight weeks, while beta-glucans made from barley or oats have been shown effective at levels between 3 to 10 g daily for up to 12 weeks.

What to Look For

Beta-glucan supplements are widely available for purchase online and are also sold in many natural-food stores and shops specializing in dietary supplements.

Many manufacturers source their beta-glucan from substances like baker's yeast. Others use medicinal mushrooms like shiitake and maitake, both of which have been found to be rich in beta-glucan. While research on the health effects of medicinal mushroom supplements is somewhat limited, a number of studies suggest that they can help boost immunity.

Look for brands tested by a trusted, independent third party, such as U.S. Pharmacopeia, NSF International, or ConsumerLab.

A Word From Verywell

Although it's too soon to recommend beta-glucan supplements for health purposes, increasing beta-glucan in your diet may help enhance your overall health.

Incorporate more oats, barley, wheat, baker's yeast, and maitake, shiitake, and reishi mushrooms in what you eat. Beta-glucan is most abundant in raw foods, but consuming grains in this state is not possible due to processing and cooking needs, which reduce the beta-glucan content.

Look for whole grains in as close to their natural states as possible. For example, choose steel-cut oats over instant oatmeal or oat flour, and pearl barley over barley flour.

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  1. Bashir KMI, Choi JS. Clinical and physiological perspectives of β-glucans: The past, present, and futureInt J Mol Sci. 2017;18(9):1906. doi:10.3390/ijms18091906

  2. Rahar S, Swami G, Nagpal N, Nagpal MA, Singh GS. Preparation, characterization, and biological properties of β-glucans. J Adv Pharm Technol Res. 2011;2(2):94-103. doi:10.4103/2231-4040.82953

  3. Othman RA, Moghadasian MH, Jones PJ. Cholesterol-lowering effects of oat β-glucan. Nutr Rev. 2011;69(6):299-309. doi:10.1111/j.1753-4887.2011.00401.x

  4. Martin SS, Blumenthal RS, Miller M. LDL cholesterol: the lower the better. Med Clin North Am. 2012;96(1):13-26. doi:10.1016/j.mcna.2012.01.009

  5. Whitehead A, Beck EJ, Tosh S, Wolever TM. Cholesterol-lowering effects of oat β-glucan: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2014;100(6):1413-21. doi:10.3945/ajcn.114.086108

  6. Francelino Andrade E, Vieira Lobato R, Vasques Araújo T, Gilberto Zangerônimo M, Vicente Sousa R, José Pereira L. Effect of beta-glucans in the control of blood glucose levels of diabetic patients: a systematic review. Nutr Hosp. 2014;31(1):170-7. doi:10.3305/nh.2015.31.1.7597

  7. Chan, G.C., Chan, W.K. & Sze, D.M. The effects of β-glucan on human immune and cancer cellsJ Hematol Oncol 2009(2);25. doi:10.1186/1756-8722-2-25

  8. Kalra S, Mukherjee JJ, Venkataraman S, et al. Hypoglycemia: The neglected complicationIndian J Endocrinol Metab. 2013;17(5):819–834. doi:10.4103/2230-8210.117219