In May 2019 researchers from Germany published a joint position paper on behalf of the Committee on Nutrition, German Society for Pediatric and Adolescent Medicine and the German Society for Pediatric Endocrinology and Diabetology on vitamin D supplementation after the second year of life, which was formulated following a review of the medical scientific literature. They stated that vitamin D supplementation can potentially reduce the risk for influenza infections as well as improving asthma exacerbations, although it has no impact on bronchial asthma severity. However, vitamin D supplementation does not appear to have any effect on attention-deficit/hyperactivity disorders, cardiac failure, hypertension, or incidence of diabetes type 2. Vitamin D supplementation also has no effect on the rate of multiple sclerosis relapses. Therefore, based on current research, routine vitamin D supplementation is not recommended for children aged after the second year of life, even when levels are below the normal range.
Reinehr T et al. Vitamin D supplementation after the second year of life: joint position paper on behalf of the Committee on Nutrition, German Society for Pediatric and Adolescent Medicine (DGKJ e.V.), and the German Society for Pediatric Endocrinology and Diabetology (DGKED e.V.). Mol Cell Pediatr. 2019 May 6;6(1):3