[5][15] The degree of cholesterol reduction depends upon the particular strain of β-glucan in a range between a molecular weights of 26.8 and 3000 kD. [25], "Oat Products and Blood Cholesterol Lowering: Summary of Assessment of a Health Claim about Oat Products and Blood Cholesterol Lowering [Health Canada, 2010]", "Understanding the Physics of Functional Fibers in the Gastrointestinal Tract: An Evidence-Based Approach to Resolving Enduring Misconceptions about Insoluble and Soluble Fiber", "High-Amylose Resistant Starch Increases Hormones and Improves Structure and Function of the Gastrointestinal Tract: A Microarray Study", "Review article: dietary fibre–microbiota interactions", "Scientific Opinion on the substantiation of health claims related to beta glucans and maintenance of normal blood cholesterol concentrations (ID 754, 755, 757, 801, 1465, 2934) and maintenance or achievement of a normal body weight (ID 820, 823) pursuant to Article 13(1) of Regulation (EC) No 1924/2006", "Cholesterol-lowering effects of oat β-glucan", "Effect of Oat β-Glucan Intake on Glycaemic Control and Insulin Sensitivity of Diabetic Patients: A Meta-Analysis of Randomized Controlled Trials", https://en.wikipedia.org/w/index.php?title=Oat_beta-glucan&oldid=979161371, Creative Commons Attribution-ShareAlike License, On the basis of the data available, the Panel concludes that a cause-and-effect relationship has been established between the consumption of beta-glucans and the "reduction of blood cholesterol concentrations.". 1160/2011 of the Commission, foodstuffs through which 3 g/day of oat beta-glucan are consumed (1 g of oat beta-glucan per portion) are allowed to display the following health claim: "Oat beta-glucan reduces the cholesterol level in the blood. The majority of cereal β-glucan bonds consist of 3 or 4 beta-1,4 glycosidic bonds (trimers and tetramers) interconnected by 1,3 linkages. [2][3], In 1997, after reviewing 33 clinical studies performed over the previous decades, the FDA approved the claim that intaking at least 3 g of β-glucan from oats per day decreased saturated fats and reduced the risk of heart disease. Oat β-glucans are linear and linked at the 1,3 and 1,4 carbon sites. In the stomach, β-glucans swell and cause gastric distension – which is associated with the signal pathway of satiation – the feeling of fullness, leading to a decreased appetite. This health claim mobilized a dietary movement as physicians and dietitians for the first time could recommend intake of a specific food to directly combat disease. Oat beta-glucan is a soluble (dissolves in liquid) dietary fiber that is made from oats. In β-glucan, these trimers and tetramers are known as cellotriosyl and cellotetraosyl. [5][15], Intake of oat β-glucan at daily amounts of at least 3 grams lowers total and low-density lipoprotein cholesterol levels by 5 to 10% in people with normal or elevated blood cholesterol levels. The gelling ability of oat β-glucan correlates to the percentage of trimers. "[14], β-glucan lowers cholesterol by increasing the viscosity of digesta in the small intestine, although cholesterol reduction is greater in those with higher total cholesterol and LDL cholesterol in their blood. In oats, β-glucan is found mainly in the endosperm of the oat kernel, especially in the outer layers of that endosperm (a marked difference from barley, which contains β-glucan uniformly throughout the endosperm).[3]. The lower the trimer-tetramer ratio, the higher the β-glucan viscosity in solution. A more viscous internal β-glucan solution generally leads to beneficial physiological effects – including a more pronounced hypoglycemic effect and lowered cholesterol levels, and a decrease in postprandial blood glucose levels. Beta-glucan is found naturally in several foods, including oats and barley. [3][4], Cereal β-glucans - including β-glucan from oat, barley and wheat - are linear polysaccharides joined by 1,3 and 1,4 carbon linkages. This marked the first time a public health agency claimed dietary intervention can actually help prevent disease. The following wording reflects the scientific evidence: "Regular consumption of beta-glucans contributes to maintenance of normal blood cholesterol concentrations." The residual solution usually contains coextracts of hemicelluloses and proteins which can then be separated through selective precipitation. Due to their property to lower cholesterol and potentially reduce the risk of cardiovascular diseases, oat β-glucans have been assigned a qualified health claim by the European Food Safety Authority and the US Food and Drug Administration. Claims for oats and beta glucan. Following the opinion of the Panel on Dietetic Products, Nutrition and Allergies (NDA) the EFSA and the Regulation (EU) no. In β-glucan, these trimers and tetramers are known as cellotriosyl and cellotetraosyl. Studies demonstrating β-glucan's effect on delayed gastric emptying may differ due to variants in food combination, β-glucan dosage, and molecular weight, and variety of food source. Often millers only process oat cultivars with at least 4% by weight β-glucan. [9] This fermentation impacts the expression of many genes within the large intestine,[10] which further affects digestive function and cholesterol and glucose metabolism, as well as the immune system and other systemic functions. Specifically, Lactobacillus and Enterococcus are stimulated by all oat β-glucan while Bifidobacterium bacteria also stimulated by oat β-glucan oligosaccharides. In the small intestine, β-glucan may reduce starch digestibility and glucose uptake – significant in the reduction of postprandial glucose levels. The amazing oat fibre, beta glucan, has been shown to lower cholesterol. Oat β-glucans can form into a random coil structure and flow with Newtonian behaviour until they reach a critical concentration at which point they become pseudoplastic. [3] Usually β-glucan is solubilized in the extraction process with residual starch, which is then removed by hydrolysis with alpha-amylase. [24], In preliminary research, oat β-glucan is being studied for its potential immunomodulatory effects, antitumour properties, and stimulation of collagen deposition, tissue granulation, reepithelization, and macrophage infiltration in the wound healing process. In oats, β-glucan is found ma… Oat products have been used for centuries for medicinal and cosmetic purposes; however, the specific role of β-glucan was not explored until the 20th century. Oat β-glucans are water-soluble β-glucans derived from the endosperm of oat kernels known for their dietary contribution as components of soluble fiber. In order to bear the claim, foods should provide at least 3 g/d of beta-glucans from oats, oat bran, barley, barley bran, or mixtures of non-processed or minimally processed beta-glucans in one or more servings. [3], Oat β-glucans have a prebiotic effect where they selectively stimulate growth of specific strands of microbes in the colon, where the particular microbe stimulated depends on the degree of polymerization of the β-glucan. Fermentation of β-glucans by microbiote results in the production of short chain fatty acids and changes to gut microbes as well as the depolymerization and structural change of the original β-glucan. One and a half cups of cooked oats provides 3 grams of beta-gluten. In July 2009, the Scientific Committee issued the following statements:[13], In November 2011, the EU Commission published its decision in favour of oat beta-glucans with regard to Article 14 of the EC Regulation on the labelling of foodstuffs with nutrition and health claim statements permitting oat beta-glucan to be described as beneficial to health. Soluble β-glucan increases stool weight through the increase in microbial cells in the colon. [5][8][16] In one review, the net decrease in blood glucose absorption reduced postprandial blood insulin concentrations, improving insulin sensitivity. [20], Postprandial blood glucose levels become lower after consumption of a meal containing β-glucan as a result of increased gut viscosity, which delays gastric emptying and lengthens travel through the small intestine. [22] Diabetic people who increased their daily consumption of beta-glucans by more than 3 grams per day for months also lost body weight. [1] A public interest in oat β-glucan arose after its cholesterol lowering effect was reported in 1984. [3] Although more viscous β-glucans result in a more viscous solution of intestinal digesta, and thus more cholesterol uptake, after a certain molecular weight, β-glucans become less soluble and thus contribute less to solution viscosity.