Since 1997, the European Union has undergone deep changes in the scientific assessment of food-related problems. Among the immediate challenges in the near future are the scientific and technological developments and regulatory measures for the so-called "functional foods," which can positively affect the health and well- being of consumers. Obesity, whose genetic and molecular basis are increasingly understood, is now foreseen as one of the key targets for novel functional foods developments, and offers a paradigmatic example of the complexity of a biological system as a target to be controlled.