Vitamin D status and the prevalence of deficiency in lactating women from eight provinces and municipalities in China

PLoS One. 2017 Mar 23;12(3):e0174378. doi: 10.1371/journal.pone.0174378. eCollection 2017.

Abstract

Background: Vitamin D deficiency has become prevalent worldwide in recent years. However, less evidence was available for lactating women.

Objective: The purpose of the study was to understand vitamin D status and prevalence of deficiency in lactating women and associated risk factors for vitamin D deficiency from eight provinces and municipalities in China.

Methods: Lactating women within 1-10 months postpartum were recruited in 2011-2013 from eight provinces and municipalities in China. Radioimmunoassay was used to measure serum 25-hydroxyvitamin D [25(OH)D] concentration. Standardized questionnaire was used to collect information on season, living site, ethnicity and socio-demographic characteristics.

Results: Totally 2004 lactating women were recruited. The median (p25, p75) of 25(OH)D was 15.8 (10.5, 24.0) nmol/L. The prevalence of vitamin D deficiency was 85.3% as 25(OH)D <30nmol/L. Serum 25(OH)D levels of lactating women were significantly lower during October-January (14.0nmol/L) than during February-May (18.0nmol/L) (P<0.001), and were significantly higher in Dai ethnicity (22.5nmol/L) than in Hui ethnicity (Chinese Muslims) (9.0nmol/L) (P<0.001). For every 10,000 CNY annual income per capita increasing, serum 25(OH)D levels significantly increased 1.04 times (P<0.001). The odds of vitamin D deficiency in winter were 2.56 times higher than that in spring (OR 2.56, 95%CI: 1.91-3.43).

Conclusions: Vitamin D deficiency of lactating women was highly prevalent in the eight provinces and municipalities in China. It is urgent to study the strategy and intervention ways for improving vitamin D status of lactating women, especially for certain population groups during low sunlight exposure season.

MeSH terms

  • Adult
  • China / epidemiology
  • Cross-Sectional Studies
  • Female
  • Humans
  • Lactation / blood*
  • Prevalence
  • Seasons
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Vitamin D Deficiency / blood
  • Vitamin D Deficiency / epidemiology*
  • Young Adult

Substances

  • Vitamin D
  • 25-hydroxyvitamin D

Grants and funding

This study was partly supported by Chinese National Technique R & D Program (863 Projects) by titled the research and development of nutritional and fortified foods promoting growth and development (project number: 2010AA023004).