Effect of equimolar amounts of long-chain triglycerides and medium-chain triglycerides on small-bowel transit time in humans.
BACKGROUND
The use of medium-chain triglycerides in diets is limited by the frequent occurrence of diarrhea or crampy abdominal pain. Because these symptoms may result from an accelerated transit time induced by medium-chain triglycerides, we investigated the effect of equimolar amounts of long-chain triglycerides and medium-chain triglycerides on small-bowel transit time in 10 healthy subjects.


METHODS
Small-bowel transit time was measured by the lactulose hydrogen breath test after intraduodenal administration of lactulose.


RESULTS
Intraduodenal administration of 20 mmol of long-chain triglycerides per hour for 90 minutes did not alter small-bowel transit time compared with control (77 +/- 11 minutes vs 77 +/- 10 minutes, respectively), whereas intraduodenal infusion of an equimolar dose of medium-chain triglycerides significantly accelerated small-bowel transit time (59 +/- 6 minutes) compared with long-chain triglycerides and control (p < .05). In six individuals, small-bowel transit time was shorter during the administration of medium-chain triglycerides compared with control, and three of these subjects experienced abdominal symptoms. Plasma cholecystokinin levels increased significantly (p < .05) during the administration of long-chain triglycerides, from 2.6 +/- 0.3 pmol/L to a maximum of 4.3 +/- 0.6 pmol/L. No significant alterations were observed in plasma cholecystokinin levels during administration of medium-chain triglycerides or in the control experiment.


CONCLUSIONS
Although it significantly increases cholecystokinin secretion, the intraduodenal infusion of long-chain triglycerides does not affect small-bowel transit time, whereas the infusion of medium-chain triglycerides accelerates small-bowel transit time, independent of cholecystokinin.
Ledeboer
M
M
Department of Gastroenterology-Hepatology, University Hospital of Leiden, The Netherlands.
Masclee
A A
AA
Jansen
J B
JB
Lamers
C B
CB
D000328:Adult; D001944:Breath Tests; D002766:Cholecystokinin / Q000097:blood; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology*; D004386:Duodenum / Q000187:drug effects / Q000502:physiology; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007421:Intestine, Small / Q000502:physiology*; D007792:Lactulose; D008297:Male; D014280:Triglycerides / Q000008:administration & dosage / Q000494:pharmacology*
D004041:Dietary Fats; D014280:Triglycerides; D007792:Lactulose; D006859:Hydrogen; D002766:Cholecystokinin