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Vitamin D deficiency and age at menarche: a prospective study
Eduardo Villamor1, Constanza Marin, Mercedes Mora-Plazas
1Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA. villamor@umich.edu
The American Journal of Clinical Nutrition
|August 12, 2011
Summary
Vitamin D deficiency is linked to earlier onset of menstruation in girls. Lower vitamin D levels were associated with a higher probability of reaching menarche at a younger age.
Area of Science:
- Endocrinology
- Pediatric Health
- Nutritional Science
Background:
- Early menarche is a known risk factor for cardiometabolic diseases and certain cancers.
- Geographic latitude, influencing sun exposure, shows an inverse relationship with menarche age, potentially mediated by vitamin D.
Purpose of the Study:
- To investigate the association between vitamin D status and the timing of menarche in girls.
- This prospective epidemiological study was conducted in Bogota, Colombia.
Main Methods:
- Plasma 25-hydroxyvitamin D [25(OH)D] levels were measured in 242 girls (mean age 8.8 years).
- Girls were followed for a median of 30 months, with periodic inquiries about menarche occurrence and date.
- Baseline 25(OH)D concentrations were categorized as deficient (<50 nmol/L), intermediate (≥50 and <75 nmol/L), or sufficient (≥75 nmol/L).
- Time-to-event analyses were used to compare menarche incidence between groups.
Main Results:
- Girls with vitamin D deficiency had a significantly higher incidence of menarche (57%) compared to vitamin D-sufficient girls (23%).
- The mean age at menarche was younger in the deficient group (11.8 years) versus the sufficient group (12.6 years).
- Vitamin D-deficient girls had double the probability of experiencing menarche (HR: 2.05) after adjusting for age and BMI-for-age z-score.
Conclusions:
- Vitamin D deficiency is significantly associated with earlier menarche in girls.
- These findings highlight the potential role of vitamin D in pubertal development timing.
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