title: Low defaecation frequency in Taiwanese adolescents: association with dietary intake, physical activity and sedentary behaviour.
abstract: OBJECTIVE
  The objectives of this study were to estimate the prevalence of constipation, defined as less than three defaecations per week, in Taiwanese adolescents and to examine its association with the intake of vegetables, fruits and fluids; time spent on sedentary behaviour; and time spent on moderate and vigorous physical activity.
  
  
  METHODS
  This study used a questionnaire survey. The study participants were 14,626 adolescents in grades 7-12. Physical activity was measured using the International Physical Activity Questionnaire-Youth Show Card Version. Time spent on sedentary activity included studying, reading, sitting in vehicles and screen time. Consumption of fluid, fruits and vegetables was measured by asking participants to describe the average consumption of each type of food in the past 7 days.
  
  
  RESULTS
  The prevalence of defaecation frequency of < 3 times a week was 9.3%. Multivariate logistic regression analysis showed that female sex (odds ratio (OR) = 2.2), worse health status (OR = 1.3), not being overweight/obese (OR = 0.7 and 0.3 for overweight and obesity), more time spent on sedentary activity (OR = 1.0) and low intake of fluids (< 1.8 L/day; OR = 1.2), fruits (< 1 portion; OR = 1.6), vegetables (< 1 portion or 100 g; OR = 1.4) and whole-grain products (OR = 1.2) were independently associated with increased risk of low defaecation frequency.
  
  
  CONCLUSIONS
  The prevalence of low defaecation frequency was high in Taiwanese adolescents. Decreasing sedentary behaviour and increasing the intake of fluids, vegetables, fruits and whole-grain products among those adolescents with very low intake levels could be helpful in preventing and managing constipation, irrespective of body size and health status.
authors.affiliation: Institutes of Clinical and Community Health Nursing Biomedical Informatics, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Li-Yin
authors.initials: LY
authors.lastname: Chien
authors.forename: Yiing Mei
authors.initials: YM
authors.lastname: Liou
authors.forename: Polun
authors.initials: P
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D003248:Constipation / Q000453:epidemiology*; D003672:Defecation; D004032:Diet; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D009043:Motor Activity; D057185:Sedentary Behavior; D011795:Surveys and Questionnaires; D013624:Taiwan / Q000453:epidemiology