Effects of Barley β-Glucan on Obesity-related Parameters and Its Mechanism of Action

Abstract

In a human intervention study in which barley containing β-glucan was consumed, the following obesity-related indicators were improved: 1) suppression of raised postprandial blood glucose, 2) reduction of serum LDL-cholesterol concentration in hypercholesterolemic men, and 3) reduction of visceral fat area in men and women with a visceral fat area of 100 cm² or more. These results demonstrate that barley consumption is effective in improving obesity-related indicators. In animal experiments, it was thought that the likely mechanism was the inhibition of digestion and absorption of barley, which depends on the molecular weight of β-glucan, and the improvement of glucose and lipid metabolism by short-chain fatty acids derived from intestinal fermentation. It was speculated that the improvement in glucose metabolism by barley consumption was mainly due to the delayed absorption of glucose and gastrointestinal hormones, such as GLP-1, with changes in gene expression having less influence. On the other hand, it was speculated that the decrease in cholesterol concentration in the liver and serum was due to the increase in short-chain fatty acids resulting from intestinal fermentation suppressing the expression level of genes involved in cholesterol biosynthesis, including HMG-CoA reductase.

graphical abstract