There has been a lot of controversy, debate and confusion over the Dietary Guidelines for Americans (DGAs). These guidelines were created to provide Americans with evidence-based nutrition education and advice. But the report submitted by the 2015 U.S. Dietary Guidelines Advisory Committee (DGAC) earlier this year wandered far away from nutrition science and its mandate when the Committee members included recommendations on sustainability, taxation policies, nutrition labeling, among others.
Recently, an increasing number of scientists are questioning the quality of the science used by the DGAC. Dr. Joanne Slavin, a registered dietitian and professor in the University of Minnesota's Department of Food Science and Nutrition and a former member of the U.S. Dietary Guidelines Advisory Committee, voiced her concern over a shift from science-based to politically motivated recommendations in the DGAs in her Star Tribune commentary.
“Dietary recommendations should be based on the entire body of existing evidence rather than on one study with alarming headlines,” writes Slavin. She believes that using the Nutrition Evidence Library (NEL) is one of the best ways to answer any research questions since it specializes in systematic reviews and uses a “strict hierarchy of evidence and grading scheme.” But Slavin points out that the 2015 DGAC used the NEL to address only 27 percent of its research questions.
We second Slavin’s concerns. If the NEL is readily available for DGAC to use, why did the Committee only use it for a small fraction of its research questions? It is important to remember that nutrition and public health professionals, policymakers, educators and federal agencies that run food, nutrition and health programs all rely on the DGAs to provide guidance. That is why it is alarming that the DGAC based its recommendations on “moderate” evidence and “less-rigorous” research methods.
We believe the DGAs first and foremost should be based on sound science - and that they should provide recommendations that can be achievable in the real world for the majority of Americans.