Serum vitamin D levels of the natural population in eastern China

Objective To assess vitamin D levels in eastern China by a standard measurement. Methods The data were from a 2014 Survey on the Prevalence in East China for Metabolic Diseases and Risk Factors-China data base. There were 12 662 subjects included in this cross-sectional study from February 2014 to June 2016. We assessed the vitamin D levels of natural population by a standard classification in which serum 25-hydroxy vitamin D (25-OHD)<50 nmol/L was defined as vitamin D deficiency. Results The average serum 25-OHD level was (40.5±12.5)nmol/L, and there were 80.3% subjects who would be classified as vitamin D deficiency; The average serum 25-OHD level of women was significantly lower than that of men (P< 0.05); The serum 25-OHD concentrations of the <30, 30-39, 40-49, 50-59, 60-69, ≥70 age groups were 37.81(31.98-43.52)nmol/L, 39.46(33.87-45.72)nmol/L, 41.17(34.10-48.65)nmol/L, 40.67(34.20-49.02)nmol/L, 44.00(35.67-53.93)nmol/L, 44.14(34.61-55.85)nmol/L for males, and 36.86(30.52-43.75)nmol/L, 37.11(31.68-43.23)nmol/L, 36.94(30.72-43.71)nmol/L, 38.42(32.08-46.41)nmol/L, 38.58(31.04-46.21)nmol/L, 37.31(29.34-47.17)nmol/L for females in corresponding subgroups. Conclusion The prevalence of vitamin D deficiency of natural population in eastern China was common, the levels of vitamin D in women were lower than those of men. However, the vitamin D levels were tended to be increasing with the advance of age. (Chin J Endocrinol Metab, 2017, 33: 726-729) Key words: Vitamin D; 25-hydroxy vitamin D