Vitamin D deficiency is increasingly recognised in neonates, especially those born to high-risk mothers.1 Term infants at high risk of vitamin D deficiency have higher mean alkaline phosphatase (ALP) activity than controls, indicating increased bone turnover.1 Despite this, ALP activities remain within the normal range in these high-risk infants. There is little research on vitamin D deficiency in very-low-birthweight (VLBW) infants, who are at high risk of bone disease due to osteopenia of prematurity (OP) and potentially maternal or nutritional vitamin D deficiency. The increase in breast feeding with inadequate supplementation …