Smoking " pack years " concept for obesity?

A team of researchers from Australia, Denmark and Indonesia have come up with the suggestion that obesity should be measured in "obese years" or "BMI years", analogous to the " pack years " concept used for smoking.  Up to now obesity has been measured internationally only by the severity of the problem and not its duration.  To do the latter would be much more meaningful because examining the association between obesity and the risk of mortality, by considering only its severity and ignoring its duration, may have underestimated the adverse effects of the current epidemic [source: International Journal of Epidemiology]