Аннотация:Several studies have described the prevalence of vitamin D deficiency in Gulf Arab populations and focused on the physical health consequences of VTD deficiency. No work to date on this population has explored the psychological consequences of VTD deficiency or the issue of seasonal variations in deficiency and symptom severity. The aim of this study was to assess seasonal variation in depressive symptoms and 25-Hydroxyvitamin D levels, exploring the relationship between vitamin D deficiency and mood in female university students in the United Arab Emirates. A cross-sectional study design was used to assess seasonal variation in mood, and a correlational analysis to assess the relationship between vitamin D levels and depressive symptoms. Depressive symptoms were positively correlated with 25 (OH)D levels. Seasonal variation was observed for both depressive symptoms and vitamin D levels, the summer cohort having the highest levels of vitamin D deficiency and reporting greater levels of depressive symptomatology. The results support previous studies that have suggested an association between 25 (OH)D levels and depressive symptoms The observed seasonal variation supports the idea of a summer time depressive spike in the UAE, probably due to increased heat/sun avoidance rather than seasonal variations in photoperiod. These findings have implications for mental health promotion and prevention of depressive illness.