University of Warwick - Doubt about what makes us SAD

Sun-worshippers often link a lack of rays to depression, citing seasonal affective disorder (SAD) as the reason for wintertime blues. However, research at the University of Warwick suggests that the often-cited link between Vitamin D, which can be derived from sunlight, and depression may not exist. Oscar Franco, the researcher who led the study at Warwick Medical School, said a study of 3,000 volunteers found no clear association between depressive symptoms and the concentration of vitamin D in the blood.