Robinson SL, et al. - Among 273 schoolchildren aged 5–12 y enrolled in a cohort study in Bogota, Colombia, researchers examined behavior problems in adolescence in correlation with vitamin D deficiency (VDD) and vitamin D binding protein (DBP) in middle childhood. At recruitment, plasma total 25-hydroxyvitamin D and DBP were quantified. Following a median 6-y follow-up, parental report [Child Behavior Checklist] and self-report [Youth Self-Report (YSR)] were used to evaluate externalizing and internalizing behavior problems. Children with vs without VDD showed 1.8 times higher prevalence of clinical total externalizing problems. Higher YSR aggressive behavior and anxious/depressed subscale scores, as well as a higher prevalence of clinical total externalizing problems, were observed in relation to DBP level below the population median. Overall, findings revealed a link between VDD and low DBP in middle childhood and behavior problems in adolescence.