Concurrent occurrence of multiple positive lifestyle behaviors and depression among adults in the United States

BackgroundTo our knowledge, no studies have examined the dose-response association between concurrent occurrence of multiple positive health behaviors and depression. As a result, the purpose of this study was to examine the dose-response association between concurrent occurrence of lifestyle behaviors (i.e., diet, physical activity, and smoking) on depression symptoms among a national sample of U.S. adults (20–85 yr). Methods: Using data from the 2005–2006 NHANES (n=2574), diet was assessed from the healthy eating index variable; physical activity was assessed via accelerometry; smoking was assessed from cotinine levels; and depression was assessed from the Patient Health Questionnaire 9 (PHQ-9). Results: Each lifestyle behavior was independently associated with depression in the expected direction, and there was also evidence of a dose–response relationship. Compared to those having 0 positive lifestyle factors, those with 1, 2, and 3 positive lifestyle factors, respectively, were 15% (p=0.38), 67% (p=0.001), and 82% (p=0.01) less likely to be classifed as having moderate or greater depression symptoms (PHQ-9≥10). Limitations: The main limitation of this study was the cross-sectional design. Conclusion: there is a dose-response relationship between concurrent occurrence of positive lifestyle behaviors and depression symptoms.