Effects of caloric and nutrient content of oral fluids on gastric emptying in volunteers: a randomised crossover study

Background: Previous studies demonstrated conflicting results regarding the determinants of gastric emptying for fluids. Our aim was to compare gastric emptying times of fluids with different caloric and nutrient content. Methods: Healthy adult volunteers underwent gastric ultrasound assessment for 4 h after consuming beverages with different caloric and nutrient content using a crossover design (oat drink with 3% fat [310 kcal], mango juice [310 kcal], oat drink with 0.5% fat [185 kcal], and blackcurrant juice [175 kcal]). Gastric emptying time, gastric content volume, and the area under the curve (AUC) of gastric content volume -time profiles were calculated. Results: Eight females and eight males completed the study protocol. The mean (SD) gastric emptying times were 89 (32) min for blackcurrant juice, 127 (54) min for oat drink with 0.5% fat, 135 (36) min for mango juice, and 152 (40) min for oat drink with 3% fat. Gastric emptying times were slower for oat drink with 3% fat (P=0.007) and mango juice (P=0.025) than for blackcurrant juice. At 1 h after ingestion, gastric content volume was greater for mango juice (P=0.021) and oat drink with 3% fat (P=0.003) than for blackcurrant juice. The AUC was greater for oat drink with 3% fat than mango juice (P=0.029), oat drink with 0.5% fat (P=0.004), and blackcurrant juice (P=0.002), and for mango juice than blackcurrant juice (P=0.019). Conclusions: Caloric and nutrient content significantly affected gastric emptying times. A high -calorie fruit juice (mango) exhibited delayed emptying times compared with a low -calorie fruit juice (blackcurrant). Clinical trial registration: ISRCTN17147574.