There is increasing attention from the military to understand the potential benefit of enhancing service members’ meals with omega-3 nutrients to improve their overall mental health. This research warrants attention due to the increase in the number of military members returning from wars with mental health issues such as PTSD and depression, and an increasing number of military members who are medically discharged for these mental health issues. Using the 2011 DOD Health Related Behaviors Survey of Active Duty Military Personnel, we analyze the association between fish oil consumption and mental health outcomes. This analysis focuses on three outcomes that capture a service members’ state of mental health (depression, post-traumatic stress [PTS], suicide ideation), and whether service members sought mental health therapy within the past 12 months. We estimated logistic regression models where the key independent variables were various levels of fish oil use (none [reference group], light, moderate, and daily use). For each outcome, we estimated five models that include control variables in the following categories: demographics, combat exposure, lifestyle—activities, lifestyle—nutrition, and lifestyle-stress. In addition, we estimated a model on the Navy-only population to examine whether Navy personnel might exhibit different patterns than DOD as a whole. We also explore whether there are gender differences in the association between fish oil usage and mental health outcomes. The survey did not show higher fish oil consumption to be associated with lower incidences of depression, post-traumatic stress, or suicide ideation among all the services. Navy-only analysis has similar findings, except that one of the models indicated that light fish oil use lowered the likelihood of Navy personnel experiencing high PTS in the past 30 days. Our recommendations are to analyze the survey data across all years it has been given to see if there are trends, encourage the military to place more emphasis on lifestyle choices pertaining to health and nutrition, and urge the military to help service members with stress and anxiety. http://archive.org/details/associationbetwe1094548490 Lieutenant Commander, United States Navy Approved for public release; distribution is unlimited.