Bone mineralization and vitamin D/calcium intake of infants fed breast‐milk, milk‐based formula or soy‐based formula

Abstract

A cross‐sectional analysis of bone mineralization during the first year of life of infants (N=107) exclusively fed breast‐milk (BF), milk‐based formula (MF) or soy‐based formula (SF) for at least the first 4 months of life was conducted. Participants were part of the longitudinal Beginnings study. Bone mineral content (BMC) was assessed using dual‐energy X‐ray absorptiometry at 3, 6, 9 and 12 months‐of‐age. Vitamin D and calcium intake were also assessed. At 3 and 6 months, BMC/mass ratio was significantly lower for SF compared to BF and MF groups. At 9 and 12 months, MF had higher BMC/mass ratio compared to BF and SF infants (p<0.05), but BF and SF were similar. BMC significantly increased in each feeding group over time but at a higher rate for SF (30% vs. 21% and 27% for BF and MF, respectively). These results suggest that although SF infants had a lower initial BMC, their rate of bone growth was faster than in BF infants. Vitamin D and calcium intake were significantly lower in BF compared with MF and SF at all time points. There was no difference in vitamin D and calcium intake between MF and SF infants except for calcium intake at 3 months. Further work is needed to delineate the characteristics of bone mineralization in each feeding group relative to their serum vitamin D concentration and calcium deposition. Funded by USDA‐ARS CRIS # 6251‐51000‐005‐03S.