title: Adolescent girls in Maine are at risk for vitamin D insufficiency.
abstract: The objective was to determine the seasonal fluctuations in serum 25-hydroxyvitamin D (25-OHD) in a group of healthy adolescents living in a northern climate. Twenty-three 9- to 11-year-old girls participated in the study from September 2000 to March 2003. Serum 25-OHD and parathyroid hormone levels were measured each September and March. Dietary intake of vitamin D was assessed each summer and winter. Summer-sun exposure was evaluated using reports of time spent outdoors. The mean decrease in serum 25-OHD from September to March was 28%. Vitamin D insufficiency (at least one serum 25-OHD level <50 nmol/L) was observed in 11 of 23 (48%) subjects. Four of 23 subjects (17%) exhibited vitamin D insufficiency in both September and March. Mean parathyroid hormone levels increased 4 pg/mL (15%) from September to March. Vitamin D intakes need to be increased in winter at northern latitudes.
authors.affiliation: Department of Food Science and Human Nutrition, University of Maine, Orono 04469, USA. susan_sullivan@umenfa.maine.edu
authors.forename: Susan S
authors.initials: SS
authors.lastname: Sullivan
authors.forename: Clifford J
authors.initials: CJ
authors.lastname: Rosen
authors.forename: William A
authors.initials: WA
authors.lastname: Halteman
authors.forename: Tai C
authors.initials: TC
authors.lastname: Chen
authors.forename: Michael F
authors.initials: MF
authors.lastname: Holick
mesh_terms: D000293:Adolescent; D017195:Adolescent Nutritional Physiological Phenomena; D002648:Child; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008281:Maine / Q000453:epidemiology; D010281:Parathyroid Hormone / Q000097:blood; D012307:Risk Factors; D012621:Seasons; D013472:Sunlight; D014807:Vitamin D / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000097:blood*; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D