Diet and chronic constipation in children: The role of fiber

Background: Chronic constipation is one of the most common disorders in Wes tern countries and despite numerous clinical, pathophysiologic, and epidemi ologic studies its cause is still unclear. Several hypotheses have been pro posed and according to experimental studies and clinical observation, fiber intake could play a role in its pathogenesis. The purpose of this case-con trol study was to examine the possible correlation of idiopathic chronic co nstipation in children and dietary intake, particularly fiber intake. Methods: A randomized sample of children (291 children with constipation an d 1602 controls) aged 2 to 14 years was taken from three of the 52 counties of Greece. Stratification was performed on the basis of urban, rural, or s uburban location and socioeconomic status. The nutritional data were obtain ed from a 3-day dietary record and a dietary history. Statistical analysis was performed with multivariate tests, multivariate analysis of variance, d iscriminant analysis, and chi-square analysis according to the characterist ics of the correlated variables. Results: Constipated children had a lower caloric and nutrient intake (p < 0.001), lower body weight/height (p < 0.001), and higher prevalence of repo rted anorexia (p < 0.001). Discriminant analysis indicated that dietary fib er alone was independently negatively correlated with chronic constipation, despite the age and the age of onset of constipation. Relative risk also h ad a negative correlation with fiber intake (p < 0.001). Of the main fiber fractions only cellulose and pentose were independently correlated with chr onic constipation. Conclusions: Lack of fiber may play an important role in the etiology of ch ronic idiopathic constipation in children.