Send to

Choose Destination
Hepatogastroenterology. 1998 May-Jun;45(21):727-32.

Water supplementation enhances the effect of high-fiber diet on stool frequency and laxative consumption in adult patients with functional constipation.

Author information

Department of Internal Medicine, Catholic University, Policlinico A. Gemelli, Rome.



The purpose of this study was to determine the effects of a high-fiber diet and fluid supplementation in patients with functional chronic constipation.


One hundred and seventeen patients with chronic functional constipation (aged 18-50 years) were randomly divided into two treatment groups. For two months both groups consumed a standard diet providing approximately 25 g fiber per day. Group 1 (58 patients) was allowed ad libitum fluid intake, while Group 2 was instructed to drink 2 liters of mineral water per day. Compliance was monitored throughout the study and results were assessed in terms of bowel-movement frequency and laxative use.


Fiber intake was similar in the two groups, while total daily fluid intake in Group 2 (mean 2.1 liters) was significantly greater than that of Group 1 (1.1 liters)(p < 0.001). In both groups, there were statistically significant increases in stool frequency and decreases in laxative use during the two-month trial, but both changes were greater in Group 2 (stool frequency: p < 0.001 vs. Group 1; laxative use: p < 0.001 vs Group 1).


A daily fiber intake of 25 g can increase stool frequency in patients with chronic functional constipation, and this effect can be significantly enhanced by increasing fluid intake to 1.5-2.0 liters/day.

[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center