Socio-economic aspects of obesity: causes or effects?

Numerous studies in the Western world show an inverse relationship between degree of obesity and socio-economic status. The relationship is most consistent among women, but it becomes obvious when focusing on obesity in men and children. To count the low socio-economic status as a cost of obesity requires that the low status is a consequence of obesity that would not occur if obesity were prevented. A few prospective cohort studies do suggest that this may be the case. However, there is also evidence suggesting that low socio-economic status promotes development of obesity. For various methodological reasons these cohort studies should be cautiously interpreted with regard to cause-and-effect relationships. Furthermore, if obesity and low socio-economic status share some causes, this would generate similar findings, and there are no studies that clearly distinguish between these possibilities. Therefore, the cause-and-effect relationship is not yet sufficiently elucidated to count the low socio-economic status of the obese as an unambiguous cost of obesity.