Moving to a Broader Concept of Quality of Glycemic Carbohydrates

Abstract

Dietary carbohydrates are important in providing energy to humans, but carbohydrates are increasingly thought of as “bad” foods associated with obesity, diabetics and associated diseases. The objective of this report is in regard to how moderating glucose delivery profiles might be done to affect physiologic endpoints that may address these public health problems. Several projects were conducted related to this new concept. Small intestinal mucosal α-glucosidases, as the glucose generation point in digestion, were applied to hydrolyze starches and α-amylase hydrolysates in vitro to elucidate slower digesting components of starch. Alginate-based microsphere embedded with starch were developed to deposit glucose at different rates in the small intestine and glucosidase activity, feeding behavior, hypothalamic neuropeptides, and gastric emptying were examined in rat and mouse models. We also conducted studies to examine how distally release glucose affects gastric empty rate in humans. Overall, our results show that relatively small amount of glucose from glycemic carbohydrates in the diet delivered distally creates certain same and second meal physiological effects including modulation of gastric emptying rate of nutrients for digestion and absorption into the body, and reduced food intake accompanied by a lowering of the orexigenic neuropeptides of the hypothalamus. Dietary glucose, in this context, becomes a bioactive molecule as it triggers physiological responses, in addition to its major energy providing role. Our goal in future research is to develop food technologies, as well as to identify practical approaches, using whole grain or whole foods, or a mixture of food ingredient and whole food, for such carbohydrate quality health-related effects.