Does legal heritage affect obesity? The channel of motor vehicle dependence

► We examine 1990–2005 data on per capita motor vehicle ownership, obesity and legal heritage. ► Motor vehicle ownership and obesity are strongly associated in common law but not civil law countries. ► This effect is robust to a variety of cross-section and panel data econometric methods. ► Our finding contrasts with evidence suggesting common law systems achieve better economic outcomes. We find a robust relationship between motor vehicle ownership, its interaction with legal heritage and obesity in OECD countries. Our estimates indicate that an increase of 100 motor vehicles per thousand residents is associated with about a 6% point increase in obesity in common law countries, whereas it has a much smaller or insignificant impact in civil law countries. These relations hold whether we examine trend data and simple correlations, or conduct cross-section or panel data regression analysis. Our results suggest that obesity rises with motor vehicle ownership in countries following a common law tradition where individual liberty is encouraged, whereas the link is small or statistically non-existent in countries with a civil law background where the rights of the individual tend to be circumscribed by the power of the state.