Summary of Method: To evaluate the feasibility of nutrigenomics as an intervention for mental health conditions, a phase I randomized controlled trial of 24 adults with depressive disorders using a 2:1 ratio of group selection (16 in the intervention {I} group and 8 in the control {C} group) is proposed. Participants with a confirmed depressive disorder will be recruited from two local mental health clinics. Those randomized into the I group will do the gene testing and be provided personalized DNA-based dietary advice from a registered dietitian; those in the C group will also receive testing but be given general dietary advice by a registered dietitian. Pre- and post-intervention comparisons (3 and 6 weeks after a personalized nutrition plan is given) will be analyzed based on records of dietary intakes (i.e., 3 day food records and food frequency questionnaire) and psychiatric functioning (e.g., Quick Inventory of Depressive Symptomology, Hospital Anxiety and Depression Scale, Outcome Questionnaire - OQ-45). In addition, measures that track physical activity, sedentary behavior, and sleep quality as well as sociodemographics will be included as covariates.