INTRODUCTION: The study aimed to investigate the association of health practices and depressive symptoms among high school adolescents in a national representative sample of 5,409 students in Oman. METHODS: Depressive symptoms were screened in 2004 through the application of the self-report 27-item Child Depression Inventory. Health practices scale comprised a simple sum of five healthy practices, namely: sleeping seven to eight hours at night, having breakfast daily, not eating between meals, not smoking the month prior to the study, and doing physical activities more than once per week apart from attending physical education classes in school. RESULTS: Sequential logistic regression models were run to test for the change in the odds-ratio (OR) of having depressive illness with a one point increase in the healthy practices scale, after adjustment for other risk factors of depression. Health practices remained having a significant protective effect on depression (OR is 0.72, 95 percent confidence interval is 0.64-0.80) even after adjustment to other significant covariates in the last model, such as history of chronic medical or mental illness diagnosed by a doctor, high scoring in chance health locus of control (HLC), low scoring in internal HLC, poor relationships with social contacts, and physical abuse during childhood or adolescence. CONCLUSION: Findings support the protective effects of positive health practices on adolescents' depression. Publication Types: Research Support, Non-U.S. Gov't