According to their editorial, Dr. Walter Willett and Dr. David Ludwig said the dietary guidelines, which were released earlier this year, did include some important advances. These included greater transparency at the early stages of development and research, an emphasis on plant-based eating patterns, replacing trans- and saturated fats with unsaturated fats, and limiting total calories, rather than calories from fat, they said.
However, they also claim that some components of the new guidelines “lack scientific foundation and hinder progress.”
In particular, they criticized the allowance for up to half of grains to come from refined carbohydrates, “which provide many unneeded calories and cause adverse metabolic consequences”; and the new focus on reducing solid fats and added sugar (SoFAS), which they claim could be confusing to many consumers.
“The new guidelines represent a mix of progress and missed opportunities,” they wrote. “…Although important progress has been made, Americans will need to rely on multiple sources for information about diet and health until the process of formulating the guidelines is fundamentally improved.”
Willett and Ludwig recommend that future guidelines should be primarily based on foods rather than nutrients, and should explicitly state which foods should be consumed less by Americans.
“A clearer message would have been that Americans must reduce consumption of red meat, cheese, butter, and sugar, but that message would have offended powerful industries. Deep in the guidelines, diligent readers can find a recommendation to limit sugar-sweetened beverages, but these products deserve front page attention as the single greatest source of calories in the U.S. diet and an important contributor to obesity, diabetes, heart disease, gout, and dental caries,” they wrote.
The authors also recommend moving primary responsibility for the guidelines to the Institute of Medicine or the Centers for Disease Control and Prevention, in order to avoid potential conflicts of interest arising from the USDA’s task of promoting commodities.
This is not the first time that Willett and Ludwig have come out against the government’s public health policies. At a debate between leading academics and economists at Harvard last month, Willett described the Supplemental Nutrition Assistance Program (SNAP) as a “conduit for people to buy mostly junk and soda”, while Ludwig said that government’s role was “not to try and compete with the food industry but to regulate.”