title: Antioxidant vitamin status (A, E, C, and beta-carotene) in European adolescents - the HELENA Study.
abstract: BACKGROUND
  An adequate nutritional status of antioxidant vitamins (vitamins A, C, E) and b-carotene is essential especially during childhood and adolescence, because of their important roles in cell growth and development. Currently, there are no physiological reference values for blood concentration of these vitamins and b-carotene in apparently healthy European adolescents. The aim of the current study was to obtain reliable and comparable data of antioxidant vitamins and b-carotene in a cross-sectional study, within HELENA (Healthy Lifestyle in Europe by Nutrition in Adolescence), which was conducted in a representative sample of adolescents from ten European cities.
  
  
  METHODS
  From a subsample of 1,054 adolescents (males= 501) of the HELENA Cross Sectional Study with an age range of 12.5 to 17.49 years, fasting blood samples were taken and analyzed for vitamins A, E, C, and b-carotene status. As specific reference values for adolescents are missing, percentile distribution by age and sex is given.
  
  
  RESULTS
  Mean concentrations were the following: Retinol: 356.4 ± 107.9 cm/mL; alpha-tocopherol: 9.9 ± 2.1 microg/mL; vitamin C: 10.3 ± 3.3 mg/L; and b-carotene: 245.6 ± 169.6 cm/mL. Females showed higher alpha-tocopherol and vitamin C values compared with males and 17-year-old boys had higher retinol levels than the same-aged girls (p = 0.018). Retinol serum concentrations increased significantly according to age in both gender, but girls had also significantly increasing b-carotene levels by age.
  
  
  CONCLUSIONS
  For the first time, concentrations of antioxidant vitamins and pro-vitamin beta-carotene have been obtained in a representative sample of apparently healthy European adolescents. These data can contribute to the establishment of reference ranges in adolescents.
authors.affiliation: ImFINE Research Group, Department of Health and Human Performance, Faculty of Physical Activity and Sport Sciences (INEF), Universidad Politécnica de Madrid, Madrid, Spain. c.breidenassel@uni-bonn.de
authors.forename: Christina
authors.initials: C
authors.lastname: Breidenassel
authors.forename: Jara
authors.initials: J
authors.lastname: Valtueña
authors.forename: Marcela
authors.initials: M
authors.lastname: González-Gross
authors.forename: Jasmin
authors.initials: J
authors.lastname: Benser
authors.forename: Andre
authors.initials: A
authors.lastname: Spinneker
authors.forename: Luis A
authors.initials: LA
authors.lastname: Moreno
authors.forename: Stefaan
authors.initials: S
authors.lastname: de Henauw
authors.forename: Kurt
authors.initials: K
authors.lastname: Widhalm
authors.forename: Denes
authors.initials: D
authors.lastname: Molnar
authors.forename: Guiseppe
authors.initials: G
authors.lastname: Maiani
authors.forename: Peter
authors.initials: P
authors.lastname: Stehle
mesh_terms: D000293:Adolescent; D001205:Ascorbic Acid / Q000097:blood*; D002648:Child; D003430:Cross-Sectional Studies; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D009752:Nutritional Status; D012016:Reference Values; D012727:Sex Characteristics; D014801:Vitamin A / Q000097:blood*; D024502:alpha-Tocopherol / Q000097:blood*; D019207:beta Carotene / Q000097:blood*
chemical_list: D019207:beta Carotene; D014801:Vitamin A; D024502:alpha-Tocopherol; D001205:Ascorbic Acid