Dr. Ricardo Uauy challenges the classical paradigm of separating malnutrition from overnutrition by demonstrating how nutrition and lifestyle factors are tightly linked to nutrition-related chronic diseases (NRCDs). Worldwide, NRCDs including obesity, cancer and cardiovascular diseases are among the leading causes of death. Contrary to common belief, Uauy points out that these are not limited to affluent countries: indeed, low- and middle-income countries are the hardest hit. A careful examination pinpoints physical inactivity and unhealthy diets as the underlying risk factors. A more serious issue is the transmission of these behavioral factors from one generation to the next, further eroding the health of a population. By comparing the twin epidemics of obesity and malnutrition, Uauy reveals that a lifecourse approach is key to the prevention of these epidemics. The prevention of NRCDs therefore is a lifelong process that begins with optimal fetal and infant growth and extends with the promotion of healthy diets and active living throughout each stage of life.