WASHINGTON — The term “ultra processed” is ill-defined and not deeply studied and would be of questionable value as a key criterion for dietary guidance, according to The Grain Chain, a grains industry coalition.

The group’s views on ultra-processed foods were included in a lengthy letter sent to the Department of Health and Human Services (HHS) in response to a request for comments in connection with the first meetings of the 2025 Dietary Guidelines Advisory Committee. The Dietary Guidelines for Americans is published every five years jointly by the HHS and the US Department of Agriculture (USDA). The comment period began Jan. 18 this year and continues until Oct. 1, 2024.

To date, the DGAC has conducted two meetings — Feb. 9-10 and May 10. At the first, a draft list of scientific questions was reviewed by the group.

The 17-page letter includes responses to a variety of questions posed by subcommittees of the DGAC dealing with a range of subjects associated with the healthfulness of foods. Among topics addressed in the questions was the connection between various food categories and health conditions such as obesity, cardiovascular disease, type 2 diabetes, different cancers and mental health together with a series of questions about dietary patterns during pregnancy and early childhood and current patterns and of food and nutrient intakes.

The Grain Chain voiced serious misgivings about a question looking at the relationship between how much ultra-processed foods are consumed and “growth, body composition, and risk of obesity.”

“The Grain Chain and its members express concern about the emphasis on ‘ultra-processed’ foods currently being explored by the DGAC and the Departments,” the group said. “For grains, whether wheat, rice, corn, or other grains, some form of processing is necessary to make the nutrients available and digestible. First, there is no widely accepted definition of ‘ultra-processed foods.’ Additionally, much of the scientific research focused on this topic consists mainly of observational research with varying definitions of ultra-processed foods. There is a lack of randomized controlled trials (RCTs) to determine a cause-and-effect relationship on ultra-processed foods and disease risk or outcomes.”

Remaining focused on the lack of a definition for ultra-processed foods and the lack of an expert on food processing or food manufacturing on the DGAC, the Grain Chain said reservations among guidelines’ committee members were evident about the use of the NOVA system for classifying foods that are supposedly ultra-processed. The group suggested these reservations were justified and that the NOVA system, which groups food based on “their hypothesized level of processing” is not the most appropriate or evidence-based approach to promoting nutrition and public health.

“In addition, NOVA does not consider the nutrient content, nutritional value, or health benefits of a food product,” the letter continued. “For example, ‘ultra-processed foods’ as described by NOVA Category 4 are not automatically high in fat, salt, sugar, or other food additives.”

Meanwhile, The Grain Chain made the case that the benefits of food processing should be considered by the DGAC and the Departments. Grains are a case in point.

“Food processing has led to beneficial nutrients being included in foods like dietary fiber, vitamins and minerals, as well as beneficial attributes that can reduce food waste and increase shelf life,” the letter said. “Enrichment and fortification of refined grains have made significant, long-lasting contributions to improve the health of Americans. With the addition of folic acid to the enrichment formula in grains in 1998, there has been a decrease in neural tube birth defects by one-third. Would this process of adding a vital nutrient then classify a food as ‘ultra-processed’ causing potentially unintended consequences of decreased consumption of enriched grain foods, and possibly decreased intake of folic acid? This could result in negative and detrimental nutrition and public health implications, not only for folic acid, but for the other nutrients that grains provide, many of which are under consumed.”

Recommendations around the term “ultra-processed foods” could negatively impact public health and could undermine cultural and traditional food preferences.

“For example, the act of making bread or pasta, is a time-honored, authentic tradition which has been done for thousands of years,” the groups said. “During the COVID-19 pandemic, consumers found comfort in not only consuming grain foods like pasta and breads, but in making them as well.”

The Grain Chain suggested the groups either jettison the subject or study it more deeply before incorporating comments about “ultra-processed foods” into its guidance.

“We strongly discourage any DGAC or DGA recommendation related to this question that uses the NOVA classification system as a key aspect for dietary guidance,” the letter said. “If the Departments are interested in pursuing this topic further, we recommend they convene a group of nutrition scientists and researchers, with expertise in food processing and manufacturing, separate from the DGAC and DGA development process, similar to how they are addressing alcohol and sustainability.”

Other highlights from the Grain Chain letter, included comments between dietary patterns consumed and:

Whole grains intake: Calling grains an “integral part” of a healthy diet and MyPlate recommendations, the groups cautioned that USDA Economic Research Service data show poor trends in whole grains consumption. Statistics gathered by the ERS indicated that intake of whole grains between 1998 and 2018 rose only to 0.43 ounces per 1,000 calories, versus 0.4 ounces in 1998. The groups said the data highlight the value of further emphasis to increase whole grain consumptions.

Relationship between intake and obesity: The group cited a 2019 perspective published in Advances in Nutrition showing a lack of meta-analyses measuring the connection between refined grains intake and body weight or adiposity. In three systematic reviews, no clear or consistent relationship was established between refined grain intake and BMI.

Cardiovascular disease risk: The group said consumption of grains has been found to reduce the risk of cardiovascular disease (CVD). Whole grains consumption at levels up to 7.5 servings per day “reduced the risk of CVD, coronary heart disease and stroke.” More recent publications “highlight a similar correlation of refined grains and the impact on cardiovascular health.”

Type 2 diabetes risk: The Grain Chain emphasized the rising prevalence of type 2 diabetes, affecting almost 10% of the US population and accounting for 25% of US health care costs.   The letter called dietary fiber “one of the best nutrients to help control blood sugar, reduce the risk of prediabetes and type 2 diabetes,” noting fiber is found in a range of grain-based foods. Regarding enriched grains, the letter highlighted a 2022 article in Mayo Clinic Proceedings in which the author said dietary pattern research has not assessed the risk associated with “each particular food group (like refined grain) within each dietary pattern.”

Cancer risks: Both whole grains and refined grains have been found to reduce the risk of cancer, the Grain Chain said. In the case of breast cancer, a 2018 meta-analysis showed intermediate to high intake of whole grains “were associated with a modest reduction of breast cancer risk.” Better-established has been the impact of whole grain consumption on the reduced risk of colon and colorectal cancer.

Dietary patterns consumed and the risk of depression and cognitive problems: “The Grain Chain said it was pleased to see the DGAC and the Departments more “closely examine food groups and dietary patterns and the impact on mood and mental health.” The groups said studies measuring the association between whole grain intake and cognition were inconclusive, though some of the studies suggested higher intake levels of whole grains were linked to “better outcomes for mood and depression and better anxiety related scores.”

In analysis of food and beverage intake together with intakes of food groups and nutrients, the Grain Chain described grains as “nutrient dense” and a leading source of under-consumed nutrients, including dietary fiber, iron and foliate, while remaining an important source of other B vitamins. Citing 2009-12 NHANES (National Health and Nutrition Examination survey) data, the letter said grain foods account for 14% of caloric intake but 23% of dietary fiber, 34% of dietary folate, 30% of iron and 14% of magnesium — “showcasing how grains help in meeting shortfall ingredients.”

The group continued, “Similarly, breads, rolls and tortillas, and ready-to-eat cereals supplied meaningful contributions of shortfall nutrients, including dietary fiber, folate, and iron, while concurrently providing minimal amounts of nutrients to limit.”