There is a contradiction here. The most influential set of rules regarding the food we eat is the one most of us ignore. But they remain important to millions of Americans.
The Dietary Guidelines for Americans, which the federal government reviews and publishes every five years, governs federal nutrition assistance programs, from WIC for women and young children to school lunches and meals for veterans and seniors. It has had a far-reaching impact. However, 63% to 90% of Americans exceed recommended levels of added sugar, saturated fat, and sodium, depending on the nutrient. 75% are below the standards set for vegetables, fruits and dairy products.
Last week, an advisory committee of academic researchers met for two days of public debate on what should be included in the next dietary guidelines. Their draft recommendations will be sent to the U.S. Department of Health and Human Services and the U.S. Department of Agriculture, which will then release final guidance at the end of the year.
On Monday, the committee (DGAC) said alcoholic beverages were not included because groups within HHS and the National Academies of Sciences, Engineering, and Medicine are already working on the issue. Ultra-processed foods are not included in the proposed 2025-2030 guidelines for different reasons. The committee found that there was too little high-quality evidence to support the guidance.
After nearly two years of reviewing the scientific literature, it may seem like the two-day presentation yielded little tangible change, so STAT asked three experts for their thoughts.
How important are these recommendations?
Grace Chamberlin, Policy Officer, Center for Science in the Public Interest: Dietary guidelines are extremely important because they are one of the biggest tools we have to improve diet, health, and our food system in this country. In other words, dietary guidelines are said to be the north star of federal nutrition programs.
Marion Nestle, professor emeritus of nutrition and public health at New York University, said: Actually no one pays much attention to them. Also, they never change. In 1980 they said we should eat more vegetables and reduce our intake of foods high in fat, sugar and salt. They still do that.
For example, when it comes to ultra-processed foods, does it just take time to get an answer?
Nestlé: We are currently running two controlled clinical trials on ultra-processed foods, both of which show that people who eat diets based on these foods eat significantly more food than those who eat relatively unprocessed diets. It indicates that you are taking in calories. What more do we need to know? DGAC ignores these trials due to their short duration.
When I was at DGAC in 1995, we were directed to consider the science and interpret its full implications as dietary advice for the American people. This assumed that the evidence would be difficult and incomplete to interpret. That changed with the 2005 guidelines. Since then, the committee has been directed to make evidence-based recommendations, and has done just that. As the current state of ultra-processed foods shows, this is an impossible limit.
Joan Munson, Professor of Medicine at Harvard Medical School and Brigham and Women’s Hospital: I think it’s important to have rigorous evidence before giving guidelines. And what I think is one of the following our findings It was a variety of ultra-processed foods and was never a one-size-fits-all. I think ultra-processed foods will be included in the dietary guidelines for 2030. It’s probably going to take a few more years before we have enough evidence, but I think we’re moving in that direction.
Chamberlin: We generally agree with the DGAC’s draft conclusions on this topic. Further research is needed to determine what exactly drives the association between ultra-processed foods and weight gain and other health effects. So I think that’s certainly a research gap that should be addressed. Consumption of ultra-processed foods is associated with increased risk of cardiovascular disease, mortality, and type 2 diabetes. However, it is unclear which aspects of ultra-processed foods cause these health effects.
What can we do with limited evidence?
Nestlé: Everyone underestimates how difficult nutrition research is. Think about it for a moment. You can’t lock people up for decades to study what they eat under controlled conditions. You have to trust people to tell you what they eat (everyone is lying, or more politely, they don’t remember). Research is necessarily observational and cannot prove cause and effect.
Chamberlin: As long as we rely on these clinical trials, it will be difficult to reach strong conclusions given the scientific rigor and standard that DGAC only makes recommendations based on existing research. And current research lacks evidence regarding pregnancy and the postpartum period, children and adolescents, and, importantly, many racial and ethnic subgroups. What they are presenting at these public meetings, whether intentionally or not, is to make sure that the next time they do this, they have done the research necessary to form a basis for strong conclusions. I think this is a strong appeal to the research community.
What do you think the committee added to the discussion?
Chamberlin: This Dietary Guidelines Advisory Committee has done a really great job of incorporating health equity into this process. They’ve shown really amazing progress to the best of their ability in trying to integrate more diverse research samples and protocols, or in implementing specific experimental food patterns. They model the dietary patterns of such specific diets, such as the diets of American Indians and Alaska Natives.
Manson: I think the research on eating patterns was very helpful. By identifying certain patterns that allow for flexibility, such as cultural influences and cultural differences, you can avoid forcing these very restrictive types of recommendations on people. People really want freedom. They may understand that it’s better not to consume certain foods too often or as much, but they don’t want them to become completely taboo.
What am I missing?
Chamberlin: [The committee is] We are limited by the surveys that exist to ensure that we have nationally representative data. Collecting samples from diverse populations requires sufficient funding and time. This is critical to becoming more informed about culturally inclusive diets and the different conclusions disaggregated by race and ethnicity to ensure health disparities are not widening. is.
We are disappointed that DGAC did not clarify or reaffirm quantitative limits on saturated fat and added sugars. And it’s not for a lack of research or evidence-based support. They couldn’t bring it up in the meeting. So we’re definitely interested in knowing what their recommendations will be for those quantitative limits.
STAT’s chronic health coverage is supported by a grant from. bloomberg philanthropy. our financial supporter It has no role in any of our journalism decisions.