This week, the 2020 Dietary Guidelines Advisory Committee convened for its second public meeting at the US Department of Agriculture (USDA). The committee is charged with developing a scientific report that will lay the foundation for the 2020-2025 Dietary Guidelines for Americans—the ninth edition of science-based nutrition recommendations that shape the food choices made by millions of kids, parents, and seniors every day.
These meetings are designed with transparency in mind: their purpose is to grant public access to the deliberations of the full committee as it builds out research protocols and eventually shares its findings. Last week’s meeting was the second in a series of five, and the first of two opportunities for the public to deliver comments to the committee in person.
And while this week’s public meeting made it crystal clear that the committee of experts is putting in hard work, there were also clear signs of the ways in which this work has been constrained by the Trump administration, including agency Secretaries at the USDA and Department of Health and Human Services (HHS). These are our two major takeaways from the second public meeting of the committee.
1. It’s clear that the committee is putting in the work
Anyone hoping to see committee members clashing ideologies or lobbying for their diets of choice would have been disappointed. The committee, of which 16 of 20 members were present, engaged in substantive discussions for the better part of six hours. Each subcommittee delivered a presentation outlining the questions it was tasked with answering, as well as the research protocols that subcommittees have developed to begin to answer those questions. (These are available online, and will be updated with each subcommittee’s progress.) Some committee members, like Dr. Joan Sabaté, raised larger questions about the core focus of the guidelines—for example, is their objective to promote good health, with a focus on foods, or good nutritional status? But the majority of the questions posed throughout the course of the day were procedural. Things like, how do we make sure we’re including the right variables and setting the correct criteria to get the best results? Or, how can we better coordinate across subcommittees to ensure consistency? From where I sat, both the technical expertise in the room and the collaborative nature of the work—among committee members and USDA staff alike—were visible from start to finish.
2. It’s also clear that this work has been constrained by the administration
Even with the full dedication of the committee, the resulting scientific report—and the Dietary Guidelines issued thereafter—is likely to fall short of its full potential to promote public health. That’s because the Trump administration has hamstrung this committee at two critical junctions in its work: it preselected the questions the committee would address, and it limited the scope of research the committee could use.
The selection of research questions is the step that can put the rest of the Dietary Guidelines process on the right path. After all, there are hundreds of ways our diet can affect our health, and exponentially more questions about how and why. If I eat more fruits and vegetables, am I less likely to get cancer? Which types of cancer? Can I drink alcohol if my child is breastfeeding? If so, how much is safe? Choosing and prioritizing these questions so that the resulting research and recommendations maximize public health benefits is key. In previous iterations of the guidelines, the committee was asked to use its collective expertise to develop these questions. But in this cycle, the USDA and HHS developed the questions first. Though the agencies have claimed this was done to promote a deliberate and transparent process, it’s also clear that this move allowed the agencies to dodge controversial questions on topics like sustainability—with profound implications for public health.
The selection of the research that will be used to answer these questions is equally important. There’s a lot of nutrition research out there—not all of it good—and the committee needs to have the best information available to do its work. That’s why it was so puzzling when the USDA made an unprecedented decision to exclude one of four types of evidence previously used by Dietary Guidelines committees: systematic reviews from external groups. In other words, research produced by institutions like the World Health Organization—no matter how high the quality—can’t be used by the committee it to make recommendations. Instead, they will now have to rely on their own systematic review. The USDA addresses this protocol change on the Dietary Guidelines website, claiming that outside systematic reviews aren’t useful because they won’t directly address the questions the committee is considering, and won’t have the same criteria. Yet previous committees, which carefully screened external reviews for quality and relevance, were able to use these reviews to save time and more effectively address questions. In fact, the 2015 committee used such reviews and reports to answer nearly half (45%) of its research questions.
Though several comments from committee members alluded to the fact that topics had been predetermined before the committee selection, there was little mention of the limitations placed on external systematic reviews. As the subcommittees work with USDA staff to begin implementing their research plans, we’ll likely find out more about if and how this hinders the process.
The next chance to get a glimpse at the committee deliberations will be on October 24-25 in Washington, DC. In the meantime, you can learn more about some of the key science issues in the 2020 Dietary Guidelines for Americans—and how to weigh in with your own public comment—on our website.