Effects of Glutamine on Gastric Emptying of Low- and High-Nutrient Drinks in Healthy Young Subjects—Impact on Glycaemia

• Published in: Nutrients Vol. 10; no. 6; p. 739
• Main Authors: Du, Yang T., Piscitelli, Diana, Ahmad, Saima, Trahair, Laurence G., Greenfield, Jerry R., Samocha-Bonet, Dorit, Rayner, Christopher K., Horowitz, Michael, Jones, Karen L.
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 07.06.2018; MDPI
• Subjects: beef; beverages; blood glucose; blood plasma; body mass index; cross-over studies; gastric emptying; glucagon-like peptide 1; Glucose; glutamine; glycemic effect; Insulin; males; soups; ultrasonics; postprandial; glucose; insulin; glutamine; gastric emptying; glycaemia
• ISSN: 2072-6643; 2072-6643
• DOI: 10.3390/nu10060739

Glutamine is a potent stimulus for the release of glucagon-like peptide-1, which increases postprandial insulin and slows gastric emptying (GE). We determined the effects of glutamine on GE of, and glycaemic responses to, low- and high-nutrient drinks in eight healthy males (mean age 21.6 ± 0.7 years and BMI 22.9 ± 0.7 kg/m2). Participants were studied on four occasions on which they consumed either a low-nutrient (beef soup; 18 kcal) or high-nutrient (75 g dextrose; 255 kcal) drink, each with or without 30 g of glutamine (120 kcal), in a randomised, crossover design. GE (2D ultrasound), blood glucose and plasma insulin concentrations were measured concurrently. Glutamine slowed GE (half emptying time (T50)) of both low- (45 ± 3 min vs. 26 ± 2 min, p < 0.001), and high-nutrient, (100 ± 5 min vs. 77 ± 5 min, p = 0.03) drinks, however, there was no effect on GE of the high nutrient drinks when expressed as kcal/min (3.39 ± 0.21 kcal/min vs. 3.81 ± 0.20 kcal/min, p = 0.25). There was no change in blood glucose after the low-nutrient drinks with or without glutamine, despite a slight increase in plasma insulin with glutamine (p = 0.007). The rise in blood glucose following the high-nutrient drink (p = 0.0001) was attenuated during the first 60 min by glutamine (p = 0.007). We conclude that in healthy subjects, glutamine slows GE of both low- and high-nutrient drinks comparably and attenuates the rise in blood glucose after the high-nutrient glucose drink.