Effect of gastric myoelectric activity on carbohydrate absorption of fruit juice in children

Juices have a different rate of gastric emptying than other foods. This may alter the rate of delivery of carbohydrates to the small bowel for absorption. The aim of the study is to demonstrate that faster gastric emptying is associated with greater production of hydrogen through a randomized, crossover study of 39 healthy children. The electrogastrography (indicator of the gastric myoelectric activities) and breath hydrogen tests (indicator of carbohydrate malabsorption) were performed at baseline and after ingestion of 240 to 330 mt of grape or pear juice given in a random order. The cutaneous electrogastrogram was analyzed by running spectral analysis to compute pre- and postprandial period dominant power (PDP) and running spectrum total power (RSTP). Postprandial PDP and RSTP were higher (p < 0.02) in the pear juice group than in the grape juice group, suggesting higher antral myoelectric activities. Twenty three percent of the subjects had significant movement artifacts that suggested discomfort after drinking pear juice compared to 5% after grape juice (p < 0.03). Breath hydrogen lest was more frequently positive (increase > 20 part per million [ppm] above baseline) after pear juice (52.2%; mean, 36 +/- 33 ppm) than after rape juice (4.3%, 6 +/- 6 ppm). In a multiple regression analysis, the most predictive independent variable of hydrogen concentration was found to be either postpraodial PDP (r(2) = 0.24; p < 0.002), or RSTP (r(2) = 0.37; p < 0.001). Juices affect gastric myoelectric activity. Grape juice induces lower antral myoelectric activities and is better absorbed. The malabsorption of carbohydrates of juices is in part related to their effect on the gastric physiology.