equal to or greater than the 85th percentile and are either obese (5.7 percent) or at risk for obesity (16.6 percent).
These data reflect an evolving obesity epidemic, representing an enormous burden for the public health and health care systems in Mexico. The association between childhood obesity and many health risks, in both children and adults, has been consistently found. The major public health impact is the association of childhood obesity with chronic disease risks in adulthood, especially overweight and obesity, type 2 diabetes, hypertension, asthma, hyperlipidemia, cardiovascular diseases (CVD), and certain cancers. Excessive weight at younger ages has also been associated with adverse psychosocial outcomes such as low self-esteem, depression, anxiety, and impaired cognitive function, especially in adolescents, although findings have not always been consistent (Swallen et al., 2005). However, research is currently not available to demonstrate this association in Mexican children and youth.
Nutrition-related chronic diseases represent a serious public health problem for the Mexican population. According to the Organization for Economic Cooperation and Development (OECD) 2005 Health Report, one quarter (24.2 percent) of the Mexican adult population is classified as obese (OECD, 2005). Data from the most recent National Health Survey (2000) showed that nearly 8 percent of all Mexican adults over 20 years of age have type 2 diabetes and approximately 30 percent have hypertension (Olaiz et al., 2003). Moreover, type 2 diabetes and CVD are the leading causes of death in the adult Mexican population, and some small studies suggest an increasing incidence of type 2 diabetes and glucose intolerance at younger ages (Cruz et al., 2004; Rodríguez-Moran et al., 2004).
Although there has not been a comprehensive evaluation of the economic impact of obesity in Mexico, a recent analysis estimated an attributable cost of diabetes for the public health sector of approximately $317 million U.S. dollars for the year 2005, almost equally distributed between direct and indirect costs (Arredondo and Zuñiga, 2004). The increasing incidence of obesity at younger ages and the scarce public resources in the country will considerably aggravate these economic projections.
As in many developing countries, the Mexican population is in the process of an epidemiologic transition and is experiencing a double disease burden. Child mortality rates and the incidence of infectious diseases have decreased. However, statistics show a significant increase in obesity and related chronic diseases such as diabetes, hypertension, and CVD in adults. High rates of malnutrition and related problems are still observed, especially among sub-populations of Mexican children. This paradoxical situation is the result of multiple factors, partly attributed to the uneven development among different segments of the population and increased socioeconomic inequalities (Uauy et al., 2001). A closely related phenom-