Vitamin D supplementation is also recommended for children and adolescents with risk factors (obesity, reduced sunlight exposure, intestinal malabsorption, chronic hepatic or kidney disease, chronic therapies such as anticonvulsants, ketoconazole, etc.), at the dose of 600 IU/die up to 1000 IU/die in the presence of multiple risk factors [110]. Other societies recommend systematical supplementation of vitamin D during winter months [121,122,123]. In Italy, despite a high prevalence of hypovitaminosis D, there is currently no indication to conduct routine testing in healthy children and adolescents without known risk factors, nor to routinely supplement vitamin D. In case of detection of vitamin D insufficiency (<20 ng/mL), it is recommended to administer a higher dose of vitamin D (2000 IU/day for 6–8 weeks).