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.