Suman Mishra
Massey University | New Zeland
Title: Timing of fruit ingestion and blood glucose response
Biography
Biography: Suman Mishra
Abstract
Partial equal carbohydrate substitution of kiwifruit sugars for starch in foods co-ingested with whole kiwifruit (KF) leads to a substantial reduction in glycaemic response. The reduction in response appears to be due to both the exchange of fructose for glucose, and to the physical influence of undigested KF remnants on digestive processes in the foregut. As fructose consumption has been reported to promote blood glucose disposal, and KF remnants appear to retard processes that mediate absorption of starch-derived glucose from the foregut, it is possible that the ability of digestion-resistant remnants of kiwifruit
to modulate the glycaemic response to starchy food depends on the temporal proximity of the ingestion of KF and starchy staple. To test this dependence of interaction on the closeness of intakes, KF (200 g = flesh of two KF) was ingested 10 h, 90 min, 30 min before, at the same time as, or 30 min after a starch-based wheaten biscuit (WB) containing the same amount of available carbohydrate, mainly starch, as the KF. Capillary blood glucose concentrations and satiety were measured after ingestion of the foods. Partial substitution of WB by KF caused a 20–30% reduction in total glycaemic response irrespective
of the separation of KF and WB ingestion. However, ingesting KF 30 min before WB decapitated the blood glucose spike, whereas the reverse, WB ingested 30 min before KF, did not. The results suggest that both the temporal distribution of available carbohydrate (meal slowness) and differences in the composition of foods consumed at different stages in a meal may affect glycaemic response, perhaps by exerting different degrees of delay in the release of available carbohydrate from the stomach to small intestine during digestion.