High-Dose Vitamin D Shown to Improve Bone Health in Very Low Birth Weight Infants
A new study published in Frontiers in Endocrinology evaluated the effectiveness and safety of high-dose vitamin D supplementation in preterm infants with very low birth weight (VLBW). The findings suggest that providing 800 IU/day of vitamin D significantly enhances bone mineralization in this vulnerable group.
VLBW preterm infants are particularly prone to vitamin D deficiency due to reduced sunlight exposure, inadequate nutrient absorption, and limited vitamin D storage capacity. Vitamin D plays a critical role in bone development by supporting calcium and phosphate absorption and promoting osteoblast activity through molecular pathways involving VDR, RANKL, osteocalcin, and alkaline phosphatase.
To assess the impact of vitamin D supplementation, researchers conducted a retrospective study on 215 VLBW infants admitted to the NICU at Hanyang University Seoul Hospital between 2011 and 2022. The infants were split into two groups based on their supplementation: 400 IU/day (n=70) and 800 IU/day (n=145). Cholecalciferol was administered via feeding tubes starting on day 14 and continued until 36 weeks postmenstrual age.
The results were compelling. Infants who received 800 IU/day showed significantly greater bone mineral density (BMD) and bone mineral content (BMC), especially in the spine and left femur. DEXA scans confirmed improved skeletal mineralization without any signs of vitamin D toxicity. Even after adjusting for baseline differences through IPTW, the higher-dose group maintained superior outcomes in BMAD (bone mineral apparent density).
Importantly, serum 25(OH)D levels were monitored only in the high-dose group, and despite elevated levels in some cases, no adverse clinical events occurred. The data support the conclusion that 800 IU/day of vitamin D is both effective and safe for improving bone health in VLBW infants.
This study contributes valuable evidence to ongoing debates over optimal vitamin D dosing in preterm infants. While U.S. guidelines suggest 400 IU/day, the findings here support the European approach recommending 800–1,000 IU/day for better bone outcomes in this at-risk population.
