Beta Glucan: Alpha of the Fibre Family

You’ve probably heard that there’s something about oats that’s good for your heart.  Many of the health benefits of oats are attributed to a type of soluble fibre called beta-glucan. 

What Is Beta-Glucan? 

It’s a soluble fibre that dissolves in water and forms a gel in your gut. This thick gel traps cholesterol as it moves through your digestive system and then eliminates it from your body. 

Beta-glucan from oats (and barley) has been studied for decades, with enough scientific evidence compiled to support its heart-healthy benefits1. These claims are supported by regulatory agencies in the U.S., Canada, and Europe.

A 2011 report looking at studies from the previous 13 years found that oat beta-glucan significantly reduces levels of total and LDL cholesterol 2 The report authors found that 3 grams of oat beta glucan soluble fibre per day is associated with 5-10% reduction in total and LDL cholesterol in those with high cholesterol, and also in those with normal cholesterol levels.

The cholesterol-reducing effects of the beta-glucan in oats and barley are so well established that the US FDA and Health Canada allow oat and barley products to carry the “heart-healthy” label if they meet certain criteria including at least .75 gm beta glucan per serving3,4

What’s the Difference Between Beta-Glucan from Mushrooms and Oats?  

There’s another form of beta glucan found in yeast, seaweed, algae, and mushrooms such as Maitike and Reishi. These are known as beta-D-glucans.

Oat beta glucans and mushroom beta glucans have slightly different molecular structures.  These differences determine their health benefits – the beta glucan from oats more related to heart health, the beta glucans from mushrooms being investigated for immune benefit. 

What Other Health Benefits Does Oat Beta-Glucan Offer? 

When oat beta-glucan fibre enters the digestive tract, it absorbs water and becomes more viscous, slowing the transit of food in the intestines. This helps you stay full longer and slows the rate at which sugar is absorbed into the bloodstream, resulting in more stable blood sugar levels. 

These effects are confirmed by many studies with one large meta-analysis reporting that consuming more beta-glucan from oats and barley may be associated with a lower risk of developing type 2 diabetes5.

Research also suggests that oat beta-glucan behaves as a prebiotic—a type of fiber that serves as food for probiotics, beneficial microorganisms in the gut6. As such, oat beta-glucan may support gut health by feeding beneficial bacteria in the digestive tract. 

In the context of a heart-healthy diet, beta-glucan from oats and barley have a well-established supportive role in lowering cholesterol. Substantial evidence also supports oat beta-glucan’s role as a prebiotic and its ability to stabilize blood sugar. 

1.Ho HV, Sievenpiper JL, Zurbau A, Blanco Mejia S, Jovanovski E, Au-Yeung F, Jenkins AL, Vuksan V. The effect of oat β-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for CVD risk reduction: a systematic review and meta-analysis of randomised-controlled trials. Br J Nutr. 2016 Oct;116(8):1369-1382. doi: 10.1017/S000711451600341X. Epub 2016 Oct 11. PMID: 27724985.

2.Othman RA, Moghadasian MH, Jones PJ. Cholesterol-lowering effects of oat β-glucan. Nutr Rev. 2011 Jun;69(6):299-309. doi: 10.1111/j.1753-4887.2011.00401.x. PMID: 21631511.



5.McRae MP. Dietary Fiber Intake and Type 2 Diabetes Mellitus: An Umbrella Review of Meta-analyses. J Chiropr Med. 2018 Mar;17(1):44-53. doi: 10.1016/j.jcm.2017.11.002. Epub 2018 Mar 1. PMID: 29628808; PMCID: PMC5883628.

6.Xu D, Feng M, Chu Y, Wang S, Shete V, Tuohy KM, Liu F, Zhou X, Kamil A, Pan D, Liu H, Yang X, Yang C, Zhu B, Lv N, Xiong Q, Wang X, Sun J, Sun G, Yang Y. The Prebiotic Effects of Oats on Blood Lipids, Gut Microbiota, and Short-Chain Fatty Acids in Mildly Hypercholesterolemic Subjects Compared With Rice: A Randomized, Controlled Trial. Front Immunol. 2021 Dec 9;12:787797. doi: 10.3389/fimmu.2021.787797. PMID: 34956218; PMCID: PMC8697019