Federal guidance on nutrition and diet is intended to reflect the state of the science and deliver the most reliable recommendations possible according to the best available evidence. This guidance, updated and presented every 5 years in the Dietary Guidelines for Americans (DGA), serves as the basis for all federal nutrition policies and nutrition assistance programs, as well as nutrition education programs. Despite the use of the guidelines over the past 30 years, recent challenges prompted Congress to question the process by which food and nutrition guidance is developed.