RESUMEN
Vitamin D inadequacy is highly prevalent in Lebanon in young adults, school children and postmenopausal osteoporotic women. However, this prevalence has not been previously studied in university students. Three hundred and eighty-one students [mean age 23.9 +/- 3.9 years], randomly recruited from Saint- Joseph University, were included in this cross-sectional study [201 males and 180 females]. Recruitment was performed across all seasons. The mean 25 hydroxyvitamin D [25[OH]D] was 31 +/- 12.4 ng/ml. 25[OH]D was inversely correlated with BMI and waist circumference [r = - 0.18 and r = - 0.19, p < 0.001 for both variables]. 25[OH]D was significantly different between the winter season and the other seasons [p = 0.023, p = 0.001 and p < 0.0001 for spring, summer and fall respectively]. 25[OH]D was lower in men compared to women [29.01 +/- 11.23 versus 33.2 +/- 13.4, p < 0.01]. This gender difference disappears after adjustment for both season and BMI. In addition, the inverse relation between 25[OH]D and BMI was non significant in the female population. In a stepwise multilinear regression analysis using 25[OH]D as a dependent variable, season and BMI were the independent predictors of vitamin D levels [p < 0.0001 and p = 0.001 respectively]. Our results suggest that, in a population of high educational level, vitamin D status is better compared to other subgroups of the Lebanese population. In addition, we found, after adjustment for BMI and season, no gender difference in 25[OH]D levels while the winter season and a high BMI negatively affect vitamin D status