High β-Glucan Whole Grain Barley Reduces Postprandial Glycemic Response in Healthy Adults-Part One of a Randomized Controlled Trial.

BACKGROUND/OBJECTIVES: The effects of sweetened and unsweetened high β-glucan whole grain barley on postprandial blood glucose response in normoglycemic human subjects were evaluated in a randomized, controlled, crossover clinical trial.

METHODS

Sixteen healthy, over-night fasted participants were studied on four or eight separate occasions. Participants consumed an unsweetened preload condition ( = 16): white glutinous rice (WR; 0 g β-glucan), low β-glucan barley (LB; ~4 g), medium β-glucan barley (MB; ~5 g), or high β-glucan barley (HB; ~6 g); or a sweetened condition with high fructose corn syrup (HFCS; = 8): WR + 50 g HFCS, LB + 50 g HFCS, MB + 50 g HFCS, or HB + 50 g HFCS. After consuming the preload as a breakfast food, participants self-administered blood glucose tests every 15 min for four hours.

RESULTS

In both sweetened and unsweetened conditions, higher β-glucan content was associated with lower blood glucose peak response and incremental area under the curve estimates (iAUC). In comparison to the unsweetened conditions, the sweetened conditions resulted in less prominent decreases in mean blood glucose response and iAUC blood glucose as β-glucan content increased.

CONCLUSIONS

By attenuating postprandial glycemic response, high β-glucan whole grain barley foods could play a role in helping to control blood glucose.