Vitamin D Deficiency in UK South Asian Women of Childbearing Age: A Comparative Longitudinal Investigation With UK Caucasian Women

Osteoporos Int. 2013 Feb;24(2):477-88. doi: 10.1007/s00198-012-1973-2. Epub 2012 Apr 14.

Abstract

Summary: This is the first 1-year longitudinal study which assesses vitamin D deficiency in young UK-dwelling South Asian women. The findings are that vitamin D deficiency is extremely common in this group of women and that it persists all year around, representing a significant public health concern.

Introduction: There is a lack of longitudinal data assessing seasonal variation in vitamin D status in young South Asian women living in northern latitudes. Studies of postmenopausal South Asian women suggest a lack of seasonal change in 25-hydroxy vitamin D [25(OH)D], although it is unclear whether this is prevalent among premenopausal South Asians. We aimed to evaluate, longitudinally, seasonal changes in 25(OH)D and prevalence of vitamin D deficiency in young UK-dwelling South Asian women as compared with Caucasians. We also aimed to establish the relative contributions of dietary vitamin D and sun exposure in explaining serum 25(OH)D.

Methods: This is a 1-year prospective cohort study assessing South Asian (n = 35) and Caucasian (n = 105) premenopausal women living in Surrey, UK (51° N), aged 20-55 years. The main outcome measured was serum 25(OH)D concentration. Secondary outcomes were serum parathyroid hormone, self-reported dietary vitamin D intake and UVB exposure by personal dosimetry.

Results: Serum 25(OH)D <25 nmol/L was highly prevalent in South Asians in the winter (81 %) and autumn (79.2 %). Deficient status (below 50 nmol/L) was common in Caucasian women. Multi-level modelling suggested that, in comparison to sun exposure (1.59, 95 %CI = 0.83-2.35), dietary intake of vitamin D had no impact on 25(OH)D levels (-0.08, 95 %CI = -1.39 to 1.23).

Conclusions: Year-round vitamin D deficiency was extremely common in South Asian women. These findings pose great health threats regarding the adverse effects of vitamin D deficiency in pregnancy and warrant urgent vitamin D public health policy and action.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asian Continental Ancestry Group / statistics & numerical data*
  • Diet / ethnology
  • Diet / statistics & numerical data
  • England / epidemiology
  • Environmental Exposure / analysis
  • Female
  • Humans
  • Longitudinal Studies
  • Middle Aged
  • Parathyroid Hormone / blood
  • Premenopause / blood
  • Prevalence
  • Seasons
  • Sunlight
  • Ultraviolet Rays
  • Vitamin D / administration & dosage
  • Vitamin D / analogs & derivatives
  • Vitamin D / blood
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / ethnology*
  • Young Adult

Substances

  • Parathyroid Hormone
  • Vitamin D
  • 25-hydroxyvitamin D