title: [25-Hydroxyvitamin D levels in infants. Relation with breast-feeding].
abstract: OBJECTIVE
  To determine the prevalence of subclinical vitamin D deficiency among infants in Valencia, Spain (latitude 39.5 degrees N) and its relation with breast- feeding.
  
  
  METHODS
  Serum levels of calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D (25-OHD) and intact parathyroid hormone (PTH) were measured in 60 term infants aged between 1 and 6 months (mean age: 3.9 months), with no known bone, gastrointestinal or renal disease (33 exclusively breast-fed, 27 bottle-fed). Data on vitamin D supplementation and weekly direct sunlight exposure were also gathered.
  
  
  RESULTS
  All infants had normal serum calcium, phosphate and PTH levels. Five infants (8.3 %) had 25-OHD levels < 10 ng/ml (lower limit of normality) and all of these infants were breast-fed (15.1 % of the group). None of these five infants received vitamin D supplementation. Infants with vitamin D deficiency had slightly elevated serum alkaline phosphatase. Only 48 % of breast-fed infants received regular vitamin D supplementation. The mean serum 25-OHD concentration of breast-fed infants in winter (16.8 ng/ml) was significantly lower than that in bottle-fed infants in summer (23.6 ng/ml, p < 0.05).
  
  
  CONCLUSIONS
  In breast-fed infants, the association of limited sunshine exposure and poor dietary vitamin D supplementation confers a high risk of subclinical vitamin D deficiency, even in regions with a temperate climate.
authors.affiliation: Servicio de Pediatría del Hospital Universitario La Fe, Valencia, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Cabezuelo Huerta
authors.forename: S
authors.initials: S
authors.lastname: Vidal Micó
authors.forename: A
authors.initials: A
authors.lastname: Abeledo Gómez
authors.forename: P
authors.initials: P
authors.lastname: Frontera Izquierdo
mesh_terms: D001942:Breast Feeding; D006801:Humans; D007223:Infant; D015995:Prevalence; D011446:Prospective Studies; D013030:Spain / Q000453:epidemiology; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D