Effectiveness of inulin intake on indicators of chronic constipation; a meta-analysis of controlled randomized clinical trials.

BACKGROUND Constipation is an intestinal dysfunction. Prebiotics, such as inulin, can improve bowel function by positively influencing intestinal biota. AIM To analyze the scientific evidence for the role of inulin in improving bowel function in patients with chronic constipation. METHODS A meta-analysis of randomized controlled clinical trials was conducted, grounded on a literature search for the period 1995-2013 (descriptors: inulin & constipation) on PubMed, ScieLo and Central Trials Register Cochrane databases. A total of 24 articles were found, 5 of them were selected for this meta-analysis, involving 252 subjects (experimental group: n = 144, control group: n = 108). The quality of the studies was assessed using the Jadad scale. RESULTS We found a significant overall effect of inulin on stool frequency (DEM = 0.69, 95%CI: 0.04, 1.34), stool consistency (Bristol scale) (DEM = 1.07, 95% CI: 0.70, 1.45), transit time (DEM = -0.57, 95% CI: -0.99, -0.15) and hardness of stool (RR = 0.42, 95% CI: 0.26, 0.70). Pain and bloating do not improve with inulin intake. CONCLUSIONS Inulin intake has a positive effect on bowel function.