BackgroundMost epidemiological surveys paid more attention to the occurrence of depression in the elderly and adolescents, while ignored the young and middle-aged people. Besides, depression resulted from a complex interaction of heredity, biochemistry, social, psychological and biological factors. The aim of our study was to examine the prevalence of depression and the relationship between depression and lifestyle factors in Chinese adults based on a large-scale cross-sectional survey. MethodsThe Composite International Diagnostic Interview Short Form for Major Depression was used to assess the depression status of all subjects. We used multi-level generalized estimating equation model to determine the relationship between depression and lifestyles. ResultsOf the 7985 respondents, 4252 were considered as being depressive with a prevalence of 53.25%. After controlling for the cluster effect of living environment and confounding effect of demographic characteristics, the following factors increased the risk of depression: overweight(OR=1.269, 95% CI: 1.117-1.444), obesity(OR=1.415, 95%CI: 1.152-1.740), single status(OR=2.003, 95% CI: 1.635-2.457), alcohol drinking(OR=1.333, 95%CI: 1.137-1.563), sleeping less than 6h a day(OR=1.485, 95% CI: 1.267-1.743), poor sleep quality (OR=1.553, 95% CI: 1.392-1.732), feeling stressed(OR=2.133, 95% CI: 1.744-2.621), adverse life events(OR=1.513, 95% CI: 1.333-1.718),unhealthy dietary patterns(OR=1.472, 95% CI: 1.324-1.638), irregular meal times (OR=2.482, 95% CI: 2.138-2.887) and suboptimal health status(OR=7.919, 95% CI: 6.843-9.185). Those with medical insurance (OR=0.774, 95% CI: 0.649-0.921) was less likely to have depression.ConclusionsUnhealthy lifestyles were found closely associated with depression. By altering lifestyle behaviors for the better, the depressive symptoms could be effectively improved.