Association between vitamin D serum level and depression

Background: Vitamin D deficiency has been identified as a global problem and about 14% of the world population has inadequate vitamin D levels. It is a neuroactive compound, a prohormone, and highly active in a variety of body tissues including the brain. The role of vitamin D in normal bone physiology, the pathogenicity of rickets, osteomalacia, and osteoporosis has been long recognized. However, in recent years a body of evidence has accumulated associating low serum vitamin D deficiency with a myriad of pathologies including cardiovascular disease, hypertension, neurodegenerative disorders, diabetes mellitus, metabolic syndrome and even cancer. Objective: Many researches demonstrate that the brain contains huge amount of vitamin D and investigators began to be interested in its part in mental disorders. Vitamin D may be an important contributor to psychiatric illnesses so clinicians should not leave this serious issue unresolved. The aim of this review is to describe our current understanding of the association between vitamin D and depression. Method: It was conducted a systematic bibliographical research, of PubMed, MedLine literature and Cochrane database without language restriction to identify all studies concerning the association between vitamin D deficiency and mental disorders from 1995 to October 2015. Results: Our searches yielded 198 appropriate citations, from which we included 61 relevant studies. Conclusion: The repeated findings have delineated a positive correlation between vitamin D deficiency and depression. However, there is no clear consensus regarding the use of vitamin D for the treatment of depression.