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Does vitamin D status track through adolescence?

Machuene A Poopedi1, Shane A Norris2, Lisa K Micklesfield2

  • 1MRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics and Division of Orthopaedic Surgery, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa machuene.poopedi@wits.ac.za.

The American Journal of Clinical Nutrition
|September 11, 2015
PubMed
Summary

Adolescent vitamin D status (25-hydroxyvitamin D) is highly variable over time, with over half changing status categories between ages 11 and 20. A single measurement does not predict long-term vitamin D levels.

Keywords:
25-hydroxyvitamin DSouth Africaadolescencetrackingvitamin D statusz scores

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Area of Science:

  • Endocrinology
  • Nutritional Science
  • Pediatric Health

Background:

  • Long-term variability of vitamin D status in adolescents remains understudied.
  • Vitamin D is crucial for adolescent health and development.
  • Understanding vitamin D status tracking is essential for public health interventions.

Purpose of the Study:

  • To assess the tracking of 25-hydroxyvitamin D [25(OH)D] status over a 10-year period in adolescents.
  • To determine if vitamin D status measured at one point reflects long-term levels in adolescents.
  • To investigate the variability of vitamin D status in adolescents aged 11-20 years.

Main Methods:

  • Longitudinal cohort study of 99 healthy adolescents in Johannesburg, South Africa.
  • Measurement of 25-hydroxyvitamin D [25(OH)D] every 2 years from age 11 to 20.
  • Calculation of individual 25(OH)D z scores relative to age 11 values.

Main Results:

  • No significant correlation in 25(OH)D levels between early and late adolescence.
  • Significant short-term tracking observed between ages 11-13 and 15-20.
  • Over 50% of adolescents changed their vitamin D status category between ages 11 and 20.
  • One-third shifted from replete to insufficient vitamin D status.

Conclusions:

  • A single 25-hydroxyvitamin D measurement is insufficient to determine an adolescent's long-term vitamin D status.
  • Findings question the reliability of studies associating single-point vitamin D measurements with disease states.
  • Repeated monitoring of vitamin D status in adolescents is recommended for accurate health assessments.