THE EFFECT OF A FIBER FREE AND FIBER SUPPLEMENTED POLYMERIC ENTERAL DIET ON NORMAL HUMAN BOWEL FUNCTION

Although the effects of dietary fibre in a normal diet on intestinal f unction are well known, the effects of supplementing enteral diet with fibre on intestinal function are not so clear. The aims of the presen t study were two fold: firstly to compare intestinal function during i ngestion of a self selected diet and fibre free polymeric enteral diet and secondly to investigate the effect of adding the fibre source, so y polysaccharide to the same polymeric diet, on bowel function. Six he althy subjects were randomly assigned to 3 treatment periods (7 days) of a self selected diet (SSD), 21 polymeric enteral diet (ED), or 21 o f the same polymeric enteral diet supplemented with 20 g/l of soy poly saccharide fibre (SPED). Parameters measured were bowel frequency/day, mean daily wet stool weights and whole gut transit time. Highest stoo l wet weights (g/24 h +/- SEM) were obtained from subjects consuming a SSD (180.3 +/- 30.6). This was significantly higher (p < 0.02) than t hose consuming an ED (81.9 +/- 14.5) but not a SPED (123 +/- 22.3). Wh ole gut transit (h +/- SEM) on a SSD (47 +/- 5.9) was significantly (p < 0.05) quicker than on an ED (73 +/- 4.9), but not significantly dif ferent from those ingesting a SPED (54 +/- 5.5). Bowel frequency/day ( +/- SEM) in subjects consuming a SPED (1.0 +/- 0.1) was significantly (p < 0.02) higher than in subjects ingesting an ED (0.8 +/- 0.1) but w as not significantly different when compared to a SSD (1.0 +/- 0.2). W e conclude that ingestion of an ED results in significantly longer who le gut transit time, significantly decreased daily stool wet weights a nd decreased bowel frequency when compared to a SSD. The ingestion of 30 g of soy polysaccharide in a polymeric enteral diet not only tends to normalise whole gut transit time and daily stool wet weights, but a lso significantly increases bowel frequency when compared with values seen during the consumption of a fibre free polymeric enteral diet.