Fiber intake, constipation, and overweight among adolescents living in Sao Paulo city

Objective This study evaluated the dietary fiber intake of adolescents in the metropolitan area of Sao Paulo city and any association between low dietary fiber intake with constipation and overweight. Methods In total, 716 adolescents were included within the study, of whom 314 attended private school and 402 attended public school. Evaluation of fiber intake was based on a 24-h daily intake record and a frequency questionnaire. Data concerning bowel movements and height and weight measurements were also taken. Results Fiber consumption, below that recommended (“age + 5”), was found in 61.8% and 41.4% (P = 0.000) of girls attending private and public schools, respectively, and in 44.1% and 25.6% of boys (P = 0.001). Adolescents who did not eat beans on more than 4 d/wk presented a higher risk of fiber intake below that recommended (age + 5; P < 0.05), with odds ratios ranging from 10.4 to 14.2 according gender and private or public schooling. Dietary fiber intake below that recommended was associated with a greater risk (P < 0.05) toward overweight in students attending public schooling (odds ratios 2.84 and 2.95 for males and females, respectively). Low dietary fiber intake was not associated with constipation. Conclusion Intake of beans more than four times per week is associated with the appropriate level of fiber intake. Dietary fiber intake below the recommendation was not associated with constipation but was associated with being overweight among those students attending public schooling.