Prevalence of Vitamin D Deficiency and Its Related Factors Among University Students in Shiraz, Iran

BACKGROUNDS Vitamin D deficiency is a public health concern even in sunny areas, so we decided to assess the prevalence of vitamin D deficiency and its related factors among university students in Shiraz. METHODS This cross-sectional study was carried out on 254 (128 male and 126 female) university students. Demographic questionnaires and a questionnaire on exposure to sun light and sun protection were completed by the participants. Serum 25OH-vitamin D was measured using a radioimmunoassay kit. Data analysis was done using Statistical Package for Social Sciences (SPSS) software # 16. A P value less than 0.05 was considered as significant. RESULTS Mean ± standard deviation (SD) of serum 25OH-vitamin D was 49.29 ± 12.87 (nmol/l) and 27.46 ± 10.37 (nmol/l) among male and female students, respectively. 51.2% of female students were vitamin D insufficient and 44% of them had vitamin D deficiency. Prevalence of vitamin D insufficiency and marginal status among male students were 49.5 and 48%, respectively. Serum vitamin D of female students was significantly less than the males (P < 0.001). Serum vitamin D was negatively correlated to sun protection score (P < 0.001, r = 0.50), but there was no correlation between serum vitamin D and sun exposure. CONCLUSIONS Vitamin D deficiency especially among female students is alarmingly prevalent. Increasing use of sunscreen lotion and clothing style could be the main factors inhibiting endogenous vitamin D synthesis which results in its deficiency.