WASHINGTON — The success schools have enjoyed in raising student intake of whole grains underscores the potential for federal policy to positively affect consumer behavior, according to a Jan. 22 letter to the U.S. Department of Agriculture from the Grain Chain, a group of leading grain-based foods organizations.

Citing a July 2019 study, the letter uses the findings to buttress its recommendation that the 2020 Dietary Guidelines for Americans raise the guidance for daily intake of whole grains to four servings from three.

“This analysis shows that federal policy can and does affect consumer behavior,” the group wrote. “Thus, as Americans continue to under consume whole grains, the recommendation of an additional whole grain serving, while maintaining the current recommendation of three servings of enriched grains, could provide new momentum to whole grain consumption in the U.S.”

The letter was addressed to Kristin Koegel of the U.S.D.A. Food and Nutrition Service, Center for Nutrition Policy and Promotion and updated the Grain Chain’s comments to the 2020 Dietary Guidelines Advisory Committee submitted in July. The committee has been holding public meetings soliciting comments and in January began a scientific review to prepare a report for submission to the Secretaries of the U.S.D.A. and the Department of Health and Human Services.

In its July comments, the Grain Chain floated the idea of a fourth whole grains serving, which could raise total grains servings to seven from six. In the past, the guidelines have recommended the consumption of six servings of grains per day, with at least half as whole grains.

“While the benefits of whole grains are widely recognized, recommending an additional serving would provide the 2020 D.G.A.s with an opportunity to educate consumers about the importance of grains in the diet,” the group said. “This could be helpful in ‘moving the needle’ when it comes to Americans taking action to increase whole grain consumption.”

Such federal support also would send a signal to the food industry, encouraging bakers and other grain-based foods manufacturers to invest in whole grain food product research, development and marketing.

“This policy could also resonate with the restaurant and food service communities, with the opportunity for consumers to be introduced to a greater variety of whole grain offerings for meals and snacks eaten away from home,” the group said.

Published in The American Journal of Preventive Medicine, the July 2019 study cited in the letter traced changes in whole grain consumption since publication of the 2005 Dietary Guidelines for Americans and the 2012 meal standards requiring at least half of all grain foods in school lunches be whole grain-rich, meaning at least 50% whole grains.

The study found that the ratio of whole grains to total grains in schoolchildren’s diets fell between 1994 and 2006 but rose significantly following the 2012 U.S.D.A. school meal regulations.

“Specifically, the whole grain/total grain ratio from all sources fell from 9.7% (1994−1998) to 7.6% (2005−2006) before climbing to 13.5% (2013−2014),” the Grain Chain said. “Home-prepared foods topped the whole grain/total grain ratio among all sources until surpassed by school foods in 2013−2014 (17.2 vs 21.5%).”

The group suggested the committee help identify sources for whole grains in the diet, noting that ready-to-eat cereal is the top source for infants and toddlers 6 to 24 months of age and children ages 2 to 17. For adults, R.-T.-E. cereal is the No. 2 source of whole grains after bread.

The 2020 guidelines will have a heightened focus on dietary needs of infants and toddlers, and the Grain Chain shared numerous points about the importance of grains for childhood nutrition for the committee to keep in mind:

• Consumers of grain foods have higher daily intakes of protein and dietary fiber; and

• grain food consumers have higher daily calcium, magnesium, phosphorus, potassium and zinc intake than non-consumers. Infant grain consumers have higher daily folate, niacin, riboflavin, thiamin, choline, B12 and B6 intakes;

• grain foods consumers have better diet qualities as measured by the U.S.D.A. Healthy Eating Index, versus non-consumers in each of these grain categories; and

• consumers of grain foods have higher total fruit intake versus non-consumers. Infants consuming all grain foods and cooked cereals consume higher amounts of total vegetables than non-consumers.

The findings were based on what the group called the first study on infants based on NHANES 2001-2016 data (National Health and Nutrition Examination Survey). The study cautioned of unintended nutrition/food group and diet quality consequences from eliminating or reducing grain foods in the dietary of infants and toddlers.

“While staying within caloric needs and recommendations, and being sensitive to added sugars, saturated fat and sodium intake, caregivers are encouraged to select whole and enriched grain foods that contribute nutrient density,’” the group said, quoting from the study.

The letter also had positive comments regarding the May 2016 publication of a “dietary fiber” definition for the purpose of ensuring only fibers with beneficial physiological effects on human health may be declared as dietary fiber on food labels.

While only seven fibers were identified initially by the F.D.A. as qualifying for the definition, the F.D.A. offered manufacturers the ability to submit a citizen petition for consideration to be added.

“As a result of such manufacturer petitions, as of the date of these comments, F.D.A. has identified a total of 17 categories of non-digestible carbohydrates (including a broad category of mixed plant cell wall fibers) that are either included in the definition of dietary fiber, or are non-digestible carbohydrates that F.D.A. intends to propose to be added to the definition of dietary fiber,” the group said.

Because fiber has been identified as a “shortfall nutrient” in the 2015 dietary guidelines, the F.D.A. actions on fiber should be viewed as a “very positive development for consumers,” the Grain Chain said.

“As illustrated by the number of new categories of dietary fiber already identified by the agency as a result of citizen petitions, the food industry is responding favorably to the new rule through innovation and product development to explore the functionality of these recently-approved fiber sources to increase the dietary fiber content of their products,” the group said. “This change reinforces the importance of dietary fiber and the need to educate consumers on the new definition and how it appears on the food label.”

Signatories to the letter were the American Bakers Association, the American Institute of Baking, the Cereal and Grains Association, the Grain Foods Foundation, the Independent Bakers Association, the National Pasta Association, the National Association of Wheat Growers, the North American Millers’ Association, the Retail Bakers of America, the Wheat Foods Council and the USA Rice Federation.