New research supports the successful implementation of Sweden’s expansion of its mandatory vitamin D fortification in 2018. Involving 1,800 infants in Sweden, the majority of young children screened had good vitamin D status, while none had indications of deficiency. At the same time, intake of the essential nutrient was too low for some. This study assessed vitamin D status among young children following the 2018 expansion, while identifying main vitamin D sources and their climate impact.