INCREASED 25-OHVITAMIN D₃, DECREASED 25-OHVITAMIN D₂ AND NORMAL 1,25(OH)₂ VITAMIN D CONCENTRATIONS IN BREAST-FED INFANTS WITHOUT SUPPLEMENTAL VITAMIN D₂

Abstract

We hypothesized that exclusively breast-fed, white full-term infants do not require vitamin D supplements. We studied in a randomized, double blind fashion, 20 term, white infants fed exclusively human milk for 6 mos. 10 received 400 IU/day D₂ (VitD) and 10 received placebo (NoVitD). Serum concentrations of 25-OHVitD₂, 25-OHVitD₂. and 1, 25(OH)₂ VitD as well as bone mineral content (BMC) or the radius were measured at birth, 6 wks, 12 wks, and 26 wks of age. Sunshine exposure (minimal erythemic dosas [MED] of ultraviolet B light [UVB]) was monitored with polysulphone dosimeters. 250HD₂ (±SD) was higher (p<.01) in VitD vs. NoVitD (32.9±8.9 vs 2.3±1 7 ng/ml at 12 wks and 24.7±11.2 vs 2.3±1.5 at 26 wks). However, 25-OHD₃ (synthesized in skin by UVB) was lower (p<.05) in VitD vs NoVitD (8.75±8.8 vs 19.9±11.2 ng/ml at 12 wks and 13.7±12.1 vs 25.7±10.5 at 26 wks), though mean weekly sunshine exposure did not differ in the groups (0.3±0.4 vs 0.2±0.3 MED's/wk). 1,25(OH)₂ VitD was similar in the groups at 12 wks (42.4±10.4 vs 41.5±12.3 pg/ml) and 26 wks (38.7±8.2 vs 37.2±8.7). BMC did not differ in the groups at 12 wks (VitD=80±12 mg/cm, NoVitD = 87±15 mg/cm) or 26 wks (Vit D=89±17 mg/cm, NoVitD=101±18 mg/cm). We conclude that white term, breast fed infants in Wisconsin do not need supplemental VitD as assessed by serum l,25(OH₂Vit D and BMC, despite low sunshine exposure. This maybe due to NoVitD having higher serum 25OHD and thus a higher rate of synthesis and/or utilization of VitD₃ from the skin compared to VitD infants.

Log in or create a free account to read this content

Gain free access to this article, as well as selected content from this journal and more on nature.com

Access through your institution

or

Sign in or create an account

Continue with Google

Continue with ORCiD