The importance of federal dietary guidelines and the effective use of improved nutrition data were among the aims of a recent National Academies of Science study about how the guidelines are developed, according to the Brown School’s Douglas Luke, who served on the panel. The committee released its report, Evaluating the Process to Develop the Dietary Guidelines for Americans, 2020-2025, in December.
The dietary guidelines and the evidence backing them up have advanced exponentially since the days of the U.S. Department of Agriculture’s food pyramid, said Luke, the Irving Louis Horowitz Professor in Social Policy and Director of the Center for Public Health Systems Science. “We have much better data and understanding of nutrition than the early days, including the recognition that nutrition needs change over the life course,” he said. He hopes the panel’s report, mandated by Congress, will bolster confidence in the guidelines and encourage the public to follow them. The last guidelines were issued in 2020, and the USDA is now at work on the next ones, which are being developed with the U.S. Department of Health and Human Services.
“The work of this committee reaffirmed the importance of the dietary guidelines but also the need to pay attention to the integrity of the development, the transparency of the process, and the need to take advantage of scientists in diet and nutrition who are working outside of the government,” he said. Luke was asked to join the panel to provide expertise on the use of systems science and systems thinking in developing the guidelines. Nutrition scientists do that in part by using data-based “food pattern modeling” to answer questions like “What would happen if added sugars were removed from a person’s diet?” Enhancing the use of food pattern modeling was one of seven recommendations made by the committee after 18 months of analyzing the development of the 2020-25 guidelines.
Luke said he appreciated the opportunity to champion systems science in such an important area of public health. He said systems thinking is critical for advancing nutrition science, as diet and nutrition are shaped by many complex systems, including the global food system, individual biology, the built environment, and national food and nutrition policies. “Diet and nutrition are hugely important for public health and connected to a lot of commercial interests,” he said. “A lot of people pay attention.”
One of those people happens to reside at Luke’s home, where he noticed ears perking up when he talked about his service on the committee. “It was one of the few times over the dinner table my wife was interested in what I do, and she immediately suggested that I should follow the same guidelines that I helped promote,” he joked.