Effect of Routine Vitamin D Supplementation on the Physical Growth of Exclusively Breastfed Infants at Six Months of Age: An Observational Study

Introduction: Vitamin D is essential for bone mineral metabolism and for the growth and development of the skeleton. The American Academy of Paediatrics and the Indian Academy of Paediatrics recommend the administration of 400 IU per day of oral Vitamin D to all infants in the first year of life. The authors hypothesised that routine supplementation of 400 IU of Vitamin D to exclusively breastfed infants would result in better physical growth. Aim: To examine the effect of routine vitamin D supplementation (400 IU/day) on the weight, length, and head circumference of term, exclusively breastfed infants at six months of age. Materials and Methods: An observational study was conducted at Department of Paediatrics, Smt. Kashibai Navale Medical College, Pune, Maharashtra, India, from November 2018 to March 2020, comparing the weight, length, and head circumference at birth and at six months of age for 111 exclusively breastfed term, appropriate for gestational age, healthy infants who were not supplemented with oral Vitamin D (Group-I) with 111 infants who were supplemented with 400 IU of oral Vitamin D daily (Group-II). Infants who presented at the Paediatric Out-Patient Department of SKNMC, Pune at around six months of age were enrolled in the study. Birth data and anthropometry at birth were recorded from available medical records. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) version 23.0. Quantitative data were presented with the mean and standard deviation. Comparison among the study groups was done using an unpaired t-test as per the results of the normality test. Association among the study groups was assessed with the help of a Student's t-test. A p-value of