Mj. Park et al., BONE-MINERAL CONTENT IS NOT REDUCED DESPITE LOW VITAMIN-D STATUS IN BREAST MILK-FED INFANTS VERSUS COWS MILK-BASED FORMULA-FED INFANTS, The Journal of pediatrics, 132(4), 1998, pp. 641-645
The effect of low or borderline vitamin D status on bone mineralizatio
n of exclusively breast milk-fed infants has not been studied. The low
vitamin D status of Korean breast milk-fed infants may theoretically
have adverse effects on bone mineralization. Assuming that bone minera
l content (BMC) relates in part to vitamin D status, we hypothesized t
hat serum 25-hydroxyvitamin D (25-OHD) concentration and BMC would be
low, and serum osteocalcin concentration high, reflecting active bone
turnover, in breast milk- versus formula-fed infants born in the winte
r. Eighteen breast milk- and 17 formula-fed infants were recruited at
ages 2 to 5 months. The BMC of the lumbar(1-4) spine region was measur
ed by using dual energy x-ray absorptiometry. The BMC and serum osteoc
alcin levels were similar for both groups. The serum 25-OHD level was
significantly lower in breast milk- than formula-fed infants; 44% of t
he breast milk group versus 6% of the formula group had serum 25-OHD l
evels less than 28 nmol/L (11 ng/ml), the lower limit of normal. The B
MC did not correlate with the serum 25-OHD level. Thus BMC and serum o
steocalcin levels in 2- to 5-month-old infants were not different by t
ype of feeding, despite low vitamin D status in breast milk-fed infant
s. We speculate that adequate mineral absorption occurs during this pe
riod from a predominantly (vitamin D independent) passive transport me
chanism.