Abstract

We use data on food purchases to explore evidence for the existence and extent of consumer self-control problems. We show that within-person (over time) variation in diet quality is considerable and similar in magnitude to between-person variation. To assess whether this reflects self-control problems or responses to fluctuations in the economic environment, we propose a two-selves model in which food choices are a compromise between a healthy and an unhealthy self, each with well-behaved preferences. We use non-parametric revealed preference tests to show that the data are consistent with this model and we recover the portion of within-person diet quality variation due to self-control problems (separate from the portion driven by changes in the economic environment). We find the extent of self-control problems to be the highest among low income consumers.