BackgroundEvidence has accumulated for the association between low vitamin D serum concentrations and mental health disorders in both children and adults. We performed a cross-sectional analysis in a population-based sample of children and adolescents to detect associations between 25(OH)-vitamin D serum [25(OH)D] concentrations and scores of the five Strengths and Difficulties Questionnaire (SDQ) subscales and the total difficulties score in different age groups (age ≥3-<12 years and ≥12-<18 years).Methods9068 participants of the population-based, nation-wide German Health Interview and Examination Survey for Children and Adolescents (KIGGS) with information on mental health status assessed by the SDQ and 25(OH)D levels were included in the analysis. For statistical analysis we used linear regression models stratified by gender based on different adjustment sets. For the younger subsample the analysis was additionally adjusted for the frequency of playing outside. We compared the associations based on parent- and self-ratings of the SDQ for children and adolescents aged ≥12-<18 years.ResultsWe found inverse associations between 25(OH)D concentrations and the subscales emotional problems, peer relationship problems and the total difficulties score in both genders after adjustment for potential confounders. The strongest associations were observed in the older subsample for parent-ratings in boys and self-ratings in girls. In the younger subsample the associations were less strong and no longer evident after adjustment for potential confounders such as migration background, socioeconomic status and frequency of playing outside.ConclusionBased on the large-scale cross-sectional study in a German population-based sample of children and adolescents we detected inverse associations between 25(OH)D concentrations and both parent- and self-rated SDQ scores of the total difficulties scale and different subscales with the strongest association in the subsample aged ≥12-<18 years for both genders. Migration background and socioeconomic status were detected as relevant confounders. Further studies–particularly in countries with comparatively low mean 25(OH)D concentrations–in childhood and adolescence are warranted. Longitudinal studies are also necessary to infer direction of effects. Finally, RCTs in children and adolescents are required to determine whether Vitamin D is beneficial for mental health.