A longitudinal study suggested that consuming Omega-3, Docosahexaenoic acid (DHA), Eicosapentaenoic acid (EPA), Docosapentaenoic acid (DPA), and Alpha-linolenic fatty acid  through the diet can safeguard against incidence and persistence of depression. Notably, 264 million people worldwide suffer from depression, that accounts for 4.3% of the world's disease burden.

According to recent studies, the escalating prevalence of depression and the decline in Omega-3 dietary intake are related. Utilizing data from baseline and first follow-up wave of Longitudinal Study of Adult Health (ELSA-Brasil), this analysis sought to examine the connection between Omega-3 fatty acid consumption and the occurrence and maintenance of depression in adults (age 39 to 64 years) and older adults (age more than 65 years).

Notably, Food Frequency Questionnaire (FFQ) was used to assess food consumption while Clinical Interview Schedule Revised (CIS-R) was used to collect data on episodes of depression. To examine links between Omega-3 dietary intake and depression, logistic regression was performed. Omega-3 fatty acids displayed a protective effect with a 2% to 65% decrease in the possibility of maintenance of episodes of depression.

Furthermore, intake of total fatty acids and alpha-linolenic acid was linked with minimized risk for incident depressive episodes (9% and 29%, respectively). Incidence estimates showed a pivotal connection between Omega-3 and alpha-linolenic acid intake, with higher Omega-3 intake being linked with a reduced chance of having episodes of depression.