Prebiotic Fructans Effect on 1-3 Years Constipated Children's Bowel Habits

Inclusion Criteria: 1. Diagnosis of functional constipation following ROME4 criteria. 2. Subject is otherwise healthy at the time of pre-examination. 3. Subject is aged 1-3 years at the time of pre-examination. 4. Subject and caretaker are able and willing to follow the study instructions. 5. Subject is suitable for participation in the study according to the investigator/physician/study personnel. 6. Written informed consent is given by parent or legal guardian. Exclusion Criteria: 1. No legal guardian's command of any local language. 2. Organic causes of defecation disorders incl. Hirschsprung disease, Spina bifida, hypothyroidism etc. 3. Other metabolic or renal abnormalities or mental retardation (Child's mental delay). 4. Food allergies or intolerances. 5. Using drugs (e.g. antibiotics) influencing gastrointestinal function (4 weeks before run-in, 6 weeks before intervention). 6. Use of laxatives and labelled pre- and probiotics in the previous 2 weeks before the beginning of run-in (4 weeks before intervention) 7. Subjects who are currently involved or will be involved in another clinical or food study