A comparison of gastric emptying of soluble solid meals and clear fluids matched for volume and energy content: a pilot crossover study.

We previously demonstrated that the gastric emptying time of different liquids with the same volume mainly depended on their energy content, regardless of differences in composition. In this crossover study, we investigated whether the same applies when soluble solid foods are ingested with water. Ten healthy volunteers ingested one of five test diets consisting of two test meals (Calorie Mate 100 and 200 kcal) and three test solutions (water and glucose solutions of 100 and 200 kcal), each given in a volume of 400 ml, and then underwent ultrasonography to measure the gastric antral cross-sectional area every 10 min for 120 min. The gastric emptying time was defined as the time for the antral cross-sectional area to revert to its initial value. When test diets with the same energy content were ingested, the gastric emptying curves were nearly identical, regardless of whether the original form was solid or liquid. The median (IQR[range]) gastric emptying times of Calorie Mate of 100 kcal with water vs. isocaloric glucose solution were 65 (60-78 [50-80]) vs. 65 (60-70 [50-80]) min (p = 0.58), and for Calorie Mate of 200 kcal with water vs. isocaloric glucose solution they were 100 (93-108 [90-120]) vs. 105 (90-110 [90-120]) min (p = 0.54). The median (IQR [range]) for water was 40 (30-40 [30-50]) min. Energy content may be a critical determinant of the gastric emptying time when ingesting soluble solid diets with water.