The study of the relationship between diet and depression in adults

Depression is a kind of common mental disorder and nutrition has a role in its prevention and treatment. In previous studies, a relationship was found between depression and intake of some nutrients and food but the results were contradictory and the reason of these contradictions was ignoring the diet. The purpose of this review study is to determine the relationship between the diet and depression.
By using the keywords (depression OR anxiety) AND (diet OR nutrition OR food) AND (pattern OR habit OR behavior in databases of (SID, Science Direct, PubMed, Scopus Elsevier). the number of 352 articles were obtained. After removing the repeated and unrelated articles, 19 articles that were published in the time period of 2009-2015 entered the study.
From the all found studies, 4 studies were cross-sectional, 11 studies were cohort and 3 studies were case- control. In all these studies, diet was tested by food frequency questionnaire, 24 hour recall and food record. Also, depression was tested by CES-D (Centre For Epidemiologic Depression Scale) or diagnosis of doctors. In general, 2 types of diet were identified: healthy diet and unhealthy diet. Healthy diet is significantly associated with the reduction of depression while there was no relationship between unhealthy diet and depression.
The findings suggest that the receiving lots of fruit, vegetable, fish and cereal maybe associated with the reduction of depression. Although it seems that more accurate control and cohort studies are needed to confirm these findings.