OBJECTIVE: To assess differences in total fiber intake by gender, and to assess association between total fiber intake and insulin level in adolescents.   
METHOD: This study was a 10-year follow-up study on probiotic and calcium trial in children living in low-socioeconomic urban area of East Jakarta between January and March 2019. The study involved 154 adolescents aged 11-17 years. Dietary fiber intake was collected by semiquantitative food frequency questionnaire. Fasting insulin was measured. Independent T-test was used to identify differences in total fiber intake by gender. Pearson correlation coefficients was used to assess association between total fiber intake and insulin level.
RESULT: The study adolescents consisted of 84 (54,5%) girls, with the median age of 16 years. The average daily consumption of total fiber was 6.02 ± 1.46 g/1000 kcal in girls and 5.64 ± 1.46 g/1000 kcal in boys. Only 2 adolescents met Institute of Medicine daily fiber intake recommendation. There was no differences in fiber intake by gender (mean difference: 1.07, 95% CI: 0.96 – 1.19, p = 0.248). The mean fasting insulin was 15.1 ± 1.7 µIU/mL. Total fiber intake was inversely associated with insulin level (r = -0.178, p = 0.027)
CONCLUSION: Fiber intake in adolescents is far below daily recommended levels across all gender. Higher fiber intake is associated with lower insulin level. Fiber intake at recommendation levels may be associated with significant cardiometabolic benefits.