Effect of High β-glucan Barley on Postprandial Blood Glucose Levels in Subjects with Normal Glucose Tolerance: Assessment by Meal Tolerance Test and Continuous Glucose Monitoring System

Abstract

The effect of white rice (WR) mixed with high β-glucan-containing barley at 50% on improvement of postprandial blood glucose levels was assessed by meal tolerance test and continuous glucose monitoring (CGM) in 15 healthy subjects with normal glucose tolerance (age 31.6 ± 12.9 years old, 4 males and 11 females). A meal tolerance test (500 kcal) was conducted using 2 types of test meals: a test meal only with WR and a test meal WR mixed 50% barley, and the side dish was the same in both meals. Blood glucose levels of the subjects 180 minutes after ingestion of the test meals were compared. In addition, a CGM device was attached to the subjects for 2 days when the WR or barley as a staple food was provided 3 times a day for consecutive days, and the daily variation of glucose was investigated. The glucose levels 30 minutes after dietary loads and the area under the blood concentration-time curve over 180 minutes were significantly decreased in the barley consumption group. In CGM, 24-hour mean blood glucose and 24-hour standard deviation of blood glucose were also significantly decreased after ingestion of the barley. Postprandial glucose level elevation was suppressed by mixing high-β-glucan barley with WR in subjects with normal glucose tolerance.

Effect of High β-glucan Barley on Postprandial Blood Glucose and Insulin Levels in Type 2 Diabetic Patients

“…A previous study reported that intake of high β-glucan barley led to reduction in visceral fat [17]. Our previous study showed that high β-glucan barley suppressed plasma glucose level elevation and oxidant stress after meals in subjects with normal glucose tolerance [18].…”

Gamma-Polyglutamic Acid-Rich Natto Suppresses Postprandial Blood Glucose Response in the Early Phase after Meals: A Randomized Crossover Study

“…γ -PGA is a viscous substance [ 3 ], and its content is approximately eight-fold higher in HPGA natto than in LPGA natto. β-glucan, a water-soluble dietary fiber, has high viscosity [ 6 ] like γ -PGA. β-glucan increases the viscosity of the food bolus and slows down the movements in the digestive tract, which delays gastric emptying and absorption [ 18 ].…”

“…β-glucan, a water-soluble dietary fiber, is a highly viscous substance [ 5 ] similar to γ -PGA. Higa et al reported that postprandial glucose levels are suppressed in response to a mixture of high-β-glucan barley with white rice (WR) 30 min after test meal loading in healthy participants [ 6 ]. Ames et al compared the postprandial glucose levels after loading with tortillas prepared from flours with various β-glucan contents and revealed a greater decrease in the percent change in glucose levels from the baseline to 30 min after high-β-glucan treatments than that observed in response to low- and medium-β-glucan treatments [ 7 ].…”

Health benefits of barley for diabetes

“…WG barley and isolated barley β-glucan have been broadly studied for their ability to impact diabetic markers among diabetic, obese or overweight, mildly diabetic, and healthy individuals, with varying degrees of success (Chillo et al, 2011;Higa et al, 2019;Liu et al, 2015;Tosh 2013). Most of these studies also enriched or incorporated WG barley and β-glucan into various food like bread, porridge, tortillas, and pasta while evaluating their ability to exert glycemic control.…”