The effect of a polymeric enteral formula supplemented with a mixture of six fibres on normal human bowel function and colonic motility

Background and aims: Fibres with varying fermentability may improve bowel function during enteral feeding. Two studies in healthy volunteers aimed to 1) investigate effects of Nutrison Multi Fibre (NMF) on gastrointestinal function, and 2) compare effects of NMF administered orally and nasogastrically on distal colonic motor activity. Methods: (1) Ten subjects were randomly assigned to 3×7 days self-selected diet (SSD), 2 litres Nutrison Standard (NS), or 2 l NMF. Objective and subjective indices were measured. (2) Two groups (n=6) received 2×250 ml boluses of NMF 2 hourly either nasogastrically or orally. Distal colonic motility was measured for 8 h (3 pre/5 post) first bolus. Results: Whole gut transit time was prolonged during NS (P<0.05) compared with SSD or NMF. Stool wet weight was higher during SSD (P<0.05) than during NS or NMF. Bowel frequencies were comparable. NMF was well tolerated. 2. Colonic activity index was maintained after oral administration with no associated diarrhoea. Activity index decreased after nasogastric bolus (P<0.05), but recovered to higher than fasting levels (P<0.05). 5 subjects had watery stools. Conclusions: Oral NMF is well tolerated, normalises whole gut transit time and maintains colonic motility. Recovery of colonic activity after nasogastric bolus suggests a putative protective effect of NMF over a longer period of feeding.