Factors associated with risk of low dietary fiber intake in adolescents

To evaluate dietary fiber intake among adolescents and to analyze factors associated with the risk of insufficient consumption of this nutrient.

Cross-sectional study of 722 adolescents from the town of São Leopoldo, RS, Brazil. Sampling was by clusters, with a systematic randomization of 40 census sectors and residences, including all individuals aged 10 to 19 years. The adolescents' weight and height were measured and sociodemographic data on their families recorded. A 24-hour dietary recall and a frequency survey were used to assess dietary intakes. The quantity of dietary fiber in diets was calculated using Nutwin nutrition support software (Programa de Apoio à Nutrição), developed by the IT Department at Universidade Federal de São Paulo (UNIFESP). Statistical analysis was by means of logistic regression, employing a hierarchical model.

The prevalence of insufficient dietary fiber intake was 69% among girls and 49.7% for boys (p < 0.001). The determinant factors of this condition among boys were non-habitual consumption of beans (OR 2.65; 95%CI 1.05-6.68) and excessive fat intake (OR 2.67; 95%CI 11.23-5.83). For girls factors were increased age (OR 5.33; 95%CI 2.33-12.2), non-habitual consumption of beans (OR 3.01; 95%CI 1.44-6.53), excessive fat intake (OR 1.85; 95%CI 1.01-3.37), dieting for weight loss (OR 2.50; 95%CI 1.10-5.70) and presence of overweight (OR 2.06; 95%CI 1.04-4.07).

These results admit of the conclusion that excessive fat consumption and non-habitual consumption of beans are strongly linked with the risk of insufficient dietary fiber intake in both sexes and that females exhibit a greater number of risk factors for this outcome.