Associations between obesity and depression by race/ethnicity and education among women: Results from the National Health and Nutrition Examination Survey, 2005-2008

Background and Significance: Studies of the association between depression and obesity among women have not always produced consistent results, perhaps because this association only applies to specific ethnic and socioeconomic subgroups. Objective: To examine associations between depression and obesity within Non-Hispanic White, Non-Hispanic Black and Hispanic women of different educational levels. Methods: Using data from the 2005-2008 National Health and Nutrition Examination Survey (N=3,774), logistic regression models were run to test associations between obesity (operationalized as body mass index (BMI) and waist circumference (WC)) and depression, stratified on race/ethnicity and education. Results: After controlling for several demographic, behavioral and health factors, Non-Hispanic White women with ≥12 years of education and WC ≥88 cm had more than double the odds of depression compared to those with WC <88 cm (odds ratio (OR): 2.15, 95% confidence interval (CI): 1.34-3.45). A similar increase in the odds of depression was found in the same racial/ethnic and education group whose BMI was ≥25 compared to those of normal BMI (OR: 2.41, 95% CI: 1.35-4.27). Among Non-Hispanic Black women with <12 years of education, depression was negatively associated with BMI ≥30 (OR: 0.24, 95% CI: 0.07-0.75) and unassociated with WC. No associations were found among Hispanics in adjusted models, and none at all among better educated Non-Hispanic Black or less educated Non-Hispanic White women. Conclusion: It is possible that the psychological significance of obesity is culturally influenced. Other risk factors for depression may also outweigh the effect of obesity among many minority and less educated women.