Perspective: Challenges and Controversial Issues in the Dietary Guidelines for Americans, 1980-2015.

Since 1980, every edition of the Dietary Guidelines for Americans (DGAs) has recommended increased consumption of fruits, vegetables, and whole grains, but reduced consumption of saturated fat, sugars, and sodium and, therefore, their primary food sources. Every edition has generated controversy, mainly from producers of foods affected by "eat less" recommendations, particularly meat. Objections to the 2015 DGAs focused on environmental as well as scientific issues, but also on purported conflicts of interest among members of the Dietary Guidelines Advisory Committee. On this basis, critics induced Congress to authorize the National Academy of Medicine (NAM) to review the process of drawing up the guidelines. The NAM's 2017 reports should strengthen the process, but as long as science continues to support advice to reduce consumption of targeted foods, the guidelines will continue to elicit political controversy.