The panel of experts that advised the government on the 2015 Dietary Guidelines for Americans “used weak scientific standards, reversing recent efforts by the government to strengthen the scientific review process,” says a five-page article in the British Medical Journal. The new edition of the guidelines, which present the government’s advice on healthy eating, is to be released this fall. The BMJ article represented a new line of criticism of the months of preparatory work for the update. The USDA delivered a strong rebuttal.
Livestock groups, with cattle ranchers in the forefront, complained that the advisory panel exceeded its mandate when it said that Americans should eat less meat both for reasons of personal health and also due to the environmental problems connected to the production of meat. Responding the meat industry criticism, lawmakers inserted language into annual funding bills to prevent the USDA and the Health and Human Services Department, co-producers of the guidelines, from considering the panel’s recommendation that long-term sustainability of food production should be a factor in the American diet today.
The secretaries of Health and Agriculture are to appear at a House Agriculture Committee hearing on Oct 7 “to review the development of the 2015 Dietary Guidelines for Americans.”
In the BMJ article, journalist Nina Teicholz says the USDA created a Nutrition Evidence Library in 2010 to help conduct systematic reviews of studies using a standardized procedure to identify, select and evaluate relevant material. “However, in its 2015 report, the committee stated it did not use NEL reviews for more than 70 percent of the topics, including some of the most controversial topics in nutrition,” writes Teicholz. Instead, it turned to reviews provided by professional societies or conducted its own ad hoc examinations of scientific literature.
Teicholz says the advisory committee did not conduct systematic reviews on saturated fats or low-carbohydrate diets. In the end, says a BMJ news release, the committee largely stuck to the advice of three decades – eat less fat and more plant foods.
Barbara Millen, who chaired the advisory committee, told BMJ it wrongly discounted the value of expertise provided by committee members and the strong foundation of work underlying the guidelines. “The notion that every question that we posed should have an NEL is flawed,” she said. “These folks know how to do the research. People who criticize this are coming from the point of view that they don’t like the answer.”
The USDA faulted the BMJ article for a “prevalence of errors,” ranging from a misunderstanding of the origin of some of the materials used by the advisory committee to wrongly saying that meat was not listed as part of its recommended diets. “HHS and USDA required the 2015 Dietary Guidelines Advisory Committee to conduct a rigorous, systematic and transparent review of the current body of nutrition science,” said the USDA’s Center for Nutrition Policy and Promotion. The panel conducted a “19-month open process,” with its work available for examination on the Internet.