What is oat beta glucan?
Beta glucan is a soluble fibre found naturally in grains (particularly oats and barley), yeast and certain mushrooms. (Check out our article about why we need more fibre)
Oat beta glucan is mostly found in the cell walls of oat bran. Most whole grain oats contain 2 - 8% beta glucan by weight and oat bran contains 15 - 35% by weight. One and a half cups of cooked oatmeal or three packets of instant oatmeal provide 3 g of beta glucan. Oat beta-glucan contribute to many of the health benefits of eating oats. Since the late 1980s, oat beta glucan has been recognised as a beneficial dietary component through many clinical studies, including lowering blood cholesterol to reduce the risk of coronary heart disease, regulating blood sugar level and improving gut health.
What are the benefits of oat beta glucan?
- Reduces blood cholesterol
Several clinical studies have demonstrated that beta glucan can effectively reduce cholesterol.
Oat beta glucan form a viscous layer in the small intestine, inhibiting intestinal uptake of dietary cholesterol and re-absorption of bile acids. Some studies reported significant effects on blood cholesterol only 2 weeks after beginning the intervention.1
The health claims approved by the European Food Safety Authority (EFSA):
"Regular consumption of beta glucans contributes to maintenance of normal blood cholesterol concentrations.” (Article 13.1)
"Oat beta glucan has been shown to lower/reduce blood cholesterol. Blood cholesterol lowering may reduce the risk of heart disease (Article 14)." This benefit is achieved by consuming at least 3g of beta glucan per day.
- Boosts heart health
Coronary heart disease (CHD) is the one of the UK'S leading causes of death, resulting in around 64,000 deaths in the UK each year, an average of one people die every eight minutes.2
It is well established that reducing blood cholesterol reduces the risk of CHD, and the US National Cholesterol Education Program (NCEP)* estimates that each 1% reduction in LDL cholesterol reduces the risk of heart disease by 1-2%.3 Daily intake of 3g of beta glucan is associated with 3-5% reductions in bad cholesterol level and leads to relative CHD risk reduction by 3-10%.4
- Regulates blood sugar level
Oat beta-glucan has low glycaemic responses which means it doesn't negatively affect blood sugar and release energy slowly.
It could reduce the risk of developing type 2 diabetes and may help to improve blood sugar levels in people with diabetes. Research suggests that beta-glucan isn’t enough to regulate blood sugar levels alone, but it could potentially be used as a complementary method alongside a healthy diet.
- Improves digestive health
Oat beta glucans are known as what we now refer to as a prebiotic (check out our post about prebiotics vs probiotic). Eating prebiotic foods helps to maintain a healthy gut microbe ecosystem. Undigested beta-glucan serves as a valuable substrate for fermentation by colonic bacteria. These good gut bacteria ferment the prebiotic and produce short chain fatty acids. Short chain fatty acids have been shown to protect against bowel cancer. Oat fibre is fermented more slowly than inulin, resulting in less gas production.5
- Supports weight management
Oat beta-glucan may support weight management efforts through releasing energy slowly and keeping you feeling satisfied, reducing appetite and calorie intake.
- Stimulates immune system
Scientists think that beta glucan could stimulate the immune and help the body fight off disease and infection more effectively.6 However, more clinical trials are needed to support the claim.
The cholesterol-lowering effect of oat β-glucan is most likely mediated by forming a viscous layer in the small intestine, inhibiting intestinal uptake of dietary cholesterol and re-absorption of bile acids.
- Thies, F., Masson, L., Boffetta, P., & Kris-Etherton, P. (2014). Oats and CVD risk markers: A systematic literature review. British Journal of Nutrition, 112(S2), S19-S30. doi:10.1017/S0007114514002281
- BHF UK CVD Factsheet.
- National Cholesterol Education Program. Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III): Final Report. NIH Publication No. 02-5215; 2002
- Othman, Rgia A., Mohammed H. Moghadasian, and Peter JH Jones. "Cholesterol-lowering effects of oat β-glucan." Nutrition reviews6 (2011): 299-309.
- Korczak, R. and Slavin, J. (2013). Effects of Oats and β-Glucan on Gut Health. In Oats Nutrition and Technology, Y. Chu (Ed.). https://doi.org/10.1002/9781118354100.ch14
- Kim, Hyung Sook et al. “Stimulatory Effect of β-glucans on Immune Cells.” Immune network vol. 11,4 (2011): 191-5. doi:10.4110/in.2011.11.4.191