the overweight and obesity are principal determinants of health in the adults. They are also a serious economic problem for the population and the country. The objective of this study of research is to estimate of the annual medical direct cost of the excess of body weight among adults population, those which received the medical aid in the Mexican Institute of Social security (IMSS) during the years 2006. We used the database 2006 provided by the Technical Division of Statistical data in Health “Data Mart” to estimate the prevalence of the overweight and obesity, and the odds ratio and the population attributable fraction (PAF) for arterial hypertension, diabetes mellitus type II and dyslipidemia. The economic burden of the excess of body weight was calculated by multiplying the cost of each disease by the FAP; for the exercise of the year 2002 and updated for the year 2006.