We reviewed the available evidence on the role of fiber in the treatment of Functional Constipation (FC) and Irritable Bowel Syndrome (IBS) in children. The vast majority of toddlers and preschoolers do not consume enough fiber. Two of the most common reasons for consultation to a pediatric gastroenterology practice include FC and IBS. The North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) and the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) guidelines state that the evidence does not support the use of fiber supplements in the treatment of FC in children, and the Rome IV criteria do not recommend an increase in fiber consumption, in children with IBS. Despite this, in general practice, it is commonly recommended that children who experience constipation and IBS to increase their fiber intake. We conducted a systematic review of the available evidence on the role of fiber in the treatment of FC and IBS in children. Thirteen full-text articles with a total of seven hundred and twenty-three pediatric participants were included in this review. Three clinical trials found positive effects of dietary fiber for the management of IBS. Nine out of ten trials found fiber to be either more effective than placebo, or just as effective as laxative treatment. Most studies on the use of fiber for the treatment of FC and IBS have shown its benefit. However, due to the heterogeneity in study design, length of treatment, outcome measures, and amount and type of fiber, we were unable to make a definitive recommendation supporting the use of fiber for the treatment of FC and IBS in children.
Keywords: abdominal pain; children; fiber; functional constipation; irritable bowel syndrome.