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Author: Specker-B-L.  Valanis-B.  Hertzberg-V.  Edwards-N. Tsang-R-C.
Title:  Sunshine exposure and serum 25-hydroxyvitamin Dconcentrations in
        exclusively breast-fed infants.
Source: J-Pediatr. 1985 Sep.  107(3).  P 372-6.
Journal Title: JOURNAL OF PEDIATRICS.

Abstract:  "The relationship between serum 25-hydroxyvitamin D (25-OHD)
concentrations and sunshine exposure in 61 term, exclusively breast-fed
infants younger than 6 months of age was investigated.  Sunshine exposure
was quantitated using a sunshine and clothing diary, which was verified by
infant-adapted ultraviolet dosimetry.  By multiple regression techniques,
infant serum 25-OHD concentrations were significantly related to UV
exposure and maternal serum 25-OHD concentrations.  Infant 25-OHD
concentrations correlated with sunshine exposure in infants whose mothers
had low (less than 35 ng/ml) or high (greater than 35 ng/ml) serum
concentrations of 25-OHD (r = 0.70, P less than 0.001 and r = 0.53, P =
0.004, respectively).  Estimates were made to determine sunshine exposure
conditions necessary to maintain serum 25-OHD concentrations above the
lower limit of the normal range (11 ng/ml).  A conservative estimate would
be 30 minutes perweek wearing only a diaper or 2 hours a week fully
clothed without a hat."


Ginna Wall, MN, IBCLC, Lactation Services Coordinator
University of Washington Medical Center, Mailbox 356153
1959 NE Pacific Street, Seattle WA 98195
Voicemail: (206)548-6368, Fax: (206)548-7665