Comparison of the Small Bowel Motor Response to Solid and Liquid Meals in Man

Abstract

Interdigestive motor activity has been studied extensively both in the human and canine small intestine. The more irregular postprandial pattern, however, has rarely been studied. In particular, physiological studies in humans are lacking. Thus it is unknown whether the physical state of a meal affects the duration of the postprandial motor activity or contractile activity during the postprandial period. 8 healthy male volunteers, aged 19-38 years, underwent a single ambulatory 24-hour manometry study. During the study, volunteers had two physiological meals. The solid meal consisted of pasta with vegetables, and the liquid meal was a vanilla milk drink. The two meals were both palatable, isocaloric (660 kcal) and had an identical fat content (32%). Recordings were analyzed visually for phase III of the migrating motor complex and a validated computer program calculated the mean frequency and amplitude of contractions as well as the mean area under the curve (AUC). The postprandial period was significantly shorter after the liquid meal compared to the solid meal (196 ± 43 vs. 298 ± 23 min; p < 0.04). During the postprandial period, the mean incidence of contractions (2.0 ± 0.5 vs. 3.7 ± 0.4 min^-1; p < 0.02) and the mean AUC (132 ± 32 vs. 236 ± 27 mm Hg × s × min^-1; p < 0.02) were significantly lower after the liquid meal. The mean amplitude of contractions during the total postprandial period, however, was not significantly different between the two test meals (19.3 ± 0.6 vs. 18.6 ± 0.8 mm Hg). We conclude that human small bowel motor activity differs markedly between solid and liquid meals. Thus the postprandial pattern persists longer after solid meals, and this may have been due to the slower gastric emptying of solids as opposed to liquids. Furthermore the small bowel contracts far more frequently after solid meals.

Magnetic pill tracking: a novel non‐invasive tool for investigation of human digestive motility

“…In a preliminary comparison ( n = 6), the values of orocaecal transit time measured by magnet tracking and by lactulose hydrogen breath test were considerably different (394 ± 76 min and 172 ± 15 min respectively) 14 . This finding is in agreement with the results obtained with 6 mm metal particles and the lactulose test 15 , and are consistent with the fact that gastric emptying of large solids and liquids (ISB) and small bowel motor activity in response to solid and liquid meals may be different 16 . The size of the magnet likely contributes to the slow transit at the pylorus and the ileocaecal function (16B).…”

Technique of Functional and Motility Test: How to Perform Antroduodenal Manometry

“…A study using solid meal demonstrated that 300 kcal diet induced more prolonged fed response duration than 150 kcal diet (mean duration 359 minutes vs. 177 minutes, respectively), whereas 600 kcal diet failed to prolong the fed pattern duration than 300 kcal diet. The amplitude of contractions was not significantly affected by the amount of meal calories 43,44. The other studies comparing different calories and diet composition in liquid solution demonstrated that fed pattern duration was significantly prolonged with 300 kcal liquid diet than water and 600 kcal meals induced higher fed pattern duration than 300 kcal.…”

The ileal brake: A fifteen-year progress report

“…The large initial release of the meal reduces the availability of nutrient brake triggers, permitting more rapid transit during the later phase of the meal [35]. This effect is supported by the findings of Schonfeld et al [36], who observed a shorter postprandial period of motility following a liquid compared to a solid meal. In the setting of enteral feeding, the degree of hydrolysis of the administered nutrient is also important to the magnitude of the activation of the ileal brake.…”