In the United States , FD&C ( generally indicates that the FDA has approved the colorant for use in Foods , Drugs and Cosmetics ) numbers are given to approved synthetic food dyes that do not exist in nature . In the European Union , E numbers are used for all additives , both synthetic and natural , that are approved in food applications . In the United States , FD&C numbers ( which generally indicates that the FDA has approved the colorant for use in foods , drugs and cosmetics ) are given to approved synthetic food dyes that do not exist in nature , while in the European Union , E numbers are used for all additives , both synthetic and natural , that are approved in food applications .