This paper investigates the effects of international trade in food on obesity in Mexico. We classify Mexican food imports from the U.S. into healthy and unhealthy and match these with anthropometric and food expenditure survey data. We find that exposure to imports of unhealthy foods significantly contributes to the rise of obesity in Mexico. The empirical evidence also suggests that unhealthy food imports may widen health disparities between education groups. By linking trade flows to food expenditure and obesity, the paper sheds light on an important channel through which globalisation may affect health.