Concern that the DGAs are not evidence-based

“The process under which [the Guidelines] were developed clearly needs enhancing to ensure that Americans are being provided the strongest, most accurate recommendations based on the most rigorous science available.”

— Cheryl Achterberg, Dean, The Ohio State University, former member of the Dietary Guidelines Advisory Committee, “Rigorous Science Must Decide Dietary Guidelines to Combat Health Epidemics”, Roll Call (2015)

Committee} report repeatedly makes recommendations based on observational studies and surrogate end points, failing to distinguish between recommendations based on expert consensus rather than high-quality RCTs. Unfortunately, the current and past U.S. dietary guidelines represent a nearly evidence-free zone.” 
— Steven Nissen, Department Chair, Cardiovascular Medicine, Cleveland Clinic, The Annals of Internal Medicine, January 19 2016

Despite being controversial recommendations based on weak scientific evidence, the United States Department of Agriculture (USDA) created in 1980 a food pyramid and placed carbohydrates at its base.  This national nutritional experiment contributed, as we know now, to the increased prevalence of obesity.”
— Osama Hamdy, Medical Director, Joslin Diabetes Center, Harvard Medical School, Nutrition Revolution: The End of the High Carbohydrates Era for Diabetes Prevention and Management, January 11, 2015.

“Healthcare is rife with controversy, and the field of nutrition more so than many, characterised as it is by much weak science, polarised opinion, and powerful commercial interests.[4] But nutrition is perhaps one of the most important and neglected of all health disciplines, traditionally relegated to non-medical nutritionists rather than being, as we believe it deserves to be, a central part of medical training and practice. The current state of nutrition research should be a matter of grave concern to those attempting to develop evidence based health and economic policies that truly serves the public interests.”  
— Dr Fiona Godlee, Editor in Chief, The BMJ  The BMJ, December 1, 2016

“In conclusion, the recommended diets are supported by a minuscule quantity of rigorous evidence that only marginally supports claims that these diets can promote better health than alternatives.”
 Nina Teicholz, investigative science journalistThe BMJ, September 23, 2015

“Government dietary fat recommendations were untested in any trial prior to being introduced.”
— Dr. Zoe HarcombeBritish OpenHeart Journal (2015)

“Important aspects of these recommendations remain unproven, yet a dietary shift in this direction has already taken place even as overweight/obesity and diabetes have increased. Although appealing to an evidence-based methodology, the DGAC Report demonstrates several critical weaknesses, including use of an incomplete body of relevant science; inaccurately representing, interpreting, or summarizing the literature; and drawing conclusions and/or making recommendations that do not reflect the limitations or controversies in the science.” 
— Hite et al, Nutrition 2010. 

“It seems reasonable to consider…whether the guidelines can be trusted and whether they have done more harm than good.”
— David A. McCarron, University of California, Davis Wall Street Journal, op-ed, Nov. 27, 2015 

“Dietary Guidelines: Are We on the Right Path?” The DGAs are only weakly associated to better health outcomes and reduced risk of chronic disease.
— Joanne Slavin, University of Minnesota, former member of the Dietary Guidelines Advisory Committee, Nutrition and Policy (2012)

“At the end of this year, the federal government will issue a new set of dietary guidelines, but what’s clear to many in the scientific community is that the dietary guidelines report is not ready for primetime. The process under which they were developed clearly needs enhancing to ensure that Americans are being provided the strongest, most accurate recommendations based on the most rigorous science available.”
— Cheryl Achterberg, The Ohio State University, former member of the Dietary Guidelines Advisory Committee, “Rigorous Science Must Decide Dietary Guidelines to Combat Health Epidemics”, Roll Call (2015)

“… these guidelines might actually have had a negative impact on health, including our current obesity epidemic. [There’s a] possibility that these dietary guidelines might actually be endangering health is at the core of our concern about the way guidelines are currently developed and issued.”
— Paul Marantz, Albert Einstein College of Medicine, American Journal of Preventative Medicine (2008)

“Government dietary fat recommendations were untested in any trial prior to being introduced.”
— Dr. Zoe Harcombe, British OpenHeart Journal (2015)

”Despite our evidence-based review lens where we say that food policies are ‘science based,’ in reality we often let our personal biases override the scientific evidence… it may be time for a new approach to dietary guidance in the United States.” 
— Joanne Slavin, University of Minnesota, former member of the Dietary Guidelines Advisory Committee, Nutrition and Policy (2015)

“The guidelines changed how Americans eat… In place of fat, we were told to eat more carbohydrates… Americans, and food companies and restaurants, listened — our consumption of fat went down and carbs, way up. But nutrition, like any scientific field, has advanced quickly, and by 2000, the benefits of very-low-fat diets had come into question… Yet, this major change went largely unnoticed by federal food policy makers.” 
— Dariush Mozaffarian, Tufts University and David Ludwig, Harvard Medical School, “Why is the Federal Government Afraid of Fat?”, New York Times (2015)

“I and a team of researchers have studied the data that these guidelines are based on and have come to the conclusion that the data are scientifically flawed. That’s because most of the data on which dietary guidelines are based were gathered by asking people to recall what they had consumed in the recent past—something people are notoriously bad at remembering.”
— Ed Archer, University of Alabama, “The Dietary Guidelines Hoax”

“The U.S. government has been providing nutrition guidance to the public since 1980. Yet 35 years later their influence on eating habits has been negligible…If policy makers expect to influence Americans’ eating habits… things must change.”
— Cheryl Achterberg, Dean, The Ohio State University, former member of the Dietary Guidelines Advisory Committee, “Government Food Cops are Out to Lunch”, Wall Street Journal (2015)

“The low-fat–high-carbohydrate diet, promulgated vigorously by…National Institutes of Health, and American Heart Association…and by the U.S. Department of Agriculture food pyramid, may well have played an unintended role in the current epidemics of obesity, lipid abnormalities, type II diabetes, and metabolic syndromes. This diet can no longer be defended by appeal to the authority of prestigious medical organizations or by rejecting clinical experience and a growing medical literature suggesting that the much-maligned low-carbohydrate–high-protein diet may have a salutary effect on the epidemics in question.”
— Sylvan Lee Weinberg, MD, “The Diet-Heart Hypothesis: A Critique. Journal of the American College of Cardiology (2004)