Obesity and Depression: Establishing Causality
Posted: 19 Jun 2007
In this paper we present an instrumental variables estimate of the effect of obesity on depression in females. Previous research has established a significant correlation between the two. The direction of causality, however, is unclear. We use employment data from the ES202 program and prices from the American Chamber of Commerce Researchers Association (ACCRA) as a vector of instruments for obesity to examine the independent effect of obesity on depression. In conducting this analysis, we employ micro-level data from the third National Health and Nutrition Examination Survey (NHANES III), covering years 1988 to 1994, as well as data from the 1979 cohort of the Child-Young Adult National Longitudinal Survey of Youth (NLSY79). We find marginal evidence that being obese actually causes levels of depression to increase. We conclude that unobservable characteristics influencing both obesity and depression are the likely causes of the strong correlation, and that factors such as perception of one's weight possibly play a greater role in determining levels of depression.
Keywords: obesity, depression
JEL Classification: I10, I12
Suggested Citation: Suggested Citation