South America is experiencing rapid epidemiologic and nutrition transitions. In the last two to three decades, profound demographic, socio-economic and environmental changes have occurred in the region (Popkin 1994). As a result, dietary and physical activity patterns of the population have changed, influencing the epidemiologic and nutritional profiles of the countries. The epidemiologic situation in the Americas is now characterized by a reduction of communicable diseases, maternal, and perinatal diseases, and a progressive increase of non-communicable chronic diseases (i.e., cardiovascular diseases, diabetes and cancer) and injuries as causes of mortality, morbidity and disability (Albala and Vio 1995). At the same time, the nutritional profile of the region has dramatically changed. [ABSTRACT FROM AUTHOR]