Research Project: Dietary and Physical Activity Guidance for Weight Loss and Maintenance

Location: Healthy Body Weight Research

2024 Annual Report

Objectives
Objective 1: Determine whether playing a newly developed EF training program “EFfect-food choices” for 8 weeks increases EF. Objective 2: Determine whether playing “EFfect-food choices” for 8 weeks increases awareness of dietary choices, positive attitudes toward fruits and vegetables (FV), valuation of FV, consumption of FV, and lowers consumption of nutrient-poor foods and body weight. Objective 3: Determine whether changes in self-consciousness of, attitudes towards, and valuation of FV predict change in dietary intake. Objective 4: Determine the association of chronic stress with the efficacy of EF training and food valuation.

Approach
The Dietary Guidelines for Americans (DGA), which include the Physical Activity Guidelines for Americans (PAGA), is the primary U.S. government resource for weight control. We propose that chronic, low-grade inflammation (CLGI) limits weight control by acting upon physiological and behavioral factors that moderate weight control. Diet and exercise reduce CLGI and provide weight control, but no one has investigated the efficacy of the DGA and PAGA to reduce CLGI, whether reduced CLGI promotes greater weight control, and the moderating roles of physiological and behavioral factors on the association of reduced CLGI with weight control. This study will test DGA- and PAGA-induced changes in CLGI and weight control. We will also determine the relation of change in CLGI with changes in novel putative physiological (metabolic rate, cell signaling molecules) and behavioral (food and exercise reinforcement, executive function) factors on the association of reduced CLGI that moderate weight control efficacy. To accomplish this, we will conduct a 9-month trial in 224 obese adults; a 3-month controlled feeding trial with four dietary treatment arms; 1) DGA with weight loss, 2) Western diet with weight loss, 3) DGA diet weight maintenance, 4) Western diet weight maintenance. Each dietary arm will have PAGA-recommended exercise and non-exercise arms. Post-trial is a 6-month weight maintenance period with participants randomized into executive function training intervention or control. The results will inform the DGA and PAGA; thereby helping clinicians, public health workers, and policymakers to improve the health of Americans.

Progress Report
During the life of this project, ARS scientist in Grand Forks, North Dakota, developed a web-based training program, titled ‘EFfect-food choices’, that is designed to enhance executive function and improve healthful behaviors. The training program is a suite of four games intended to target both attention bias and inhibitory control. For this project, the EFfect-food choices training suite is being used to improve attitudes, perceptions, and consumption of fruits and vegetables while concurrently weakening attitudes and perceptions of high fat/high sugar energy-dense foods and decreasing their consumption. Due to the setbacks suffered during the COVID 19 pandemic, this study remains ongoing. To date, 94 participants have completed the study and 172 are actively using the EFfect-food choices program. We anticipate enrolling an additional 144 participants with an additional 76 participants completing the study before the end of FY24. This project will continue until 500 participants have completed the study. If shown effective, the EFfect-food choices program will provide a platform that can be used to increase healthy eating behaviors and, thus, improve diet quality. The capability of this training program to be broadly implemented via the internet will greatly expand the reach of interventional studies designed to aid individuals in food-related decision-making. This type of intervention is simple, inexpensive, and something that can readily be made available to the public. ARS scientists in Grand Forks, North Dakota, are participating in the ARS Grand Synergies project ‘Beef Systems Grand Challenge’ to evaluate how breed, environment, and management practices impact the nutritional quality of beef. We received 1280 beef samples and have analyzed the percentage of fat and protein of 550 beef samples. The beef samples will also be analyzed to determine the fatty acids and amino acids profiles and the micronutrient content. In continuation, scientists attended a USDA-ARS Beef Systems Research Strategy Planning Session to identify gaps and priorities for beef systems research in support of cohesive within-ARS and across-ARS sites, supporting project development and planning for future implementation, and to develop the next phase of the Beef Grand Challenge program. This research will benefit beef producers and consumers and contribute to our understanding of the role of beef cattle production on beef’s nutritional quality. ARS scientists in Grand Forks, North Dakota, are participating in a cross-sectional study being conducted at 8 sites throughout the United States to investigate the inter- and intra-device reliability of a commercially available non-invasive, portable device that is used to assess fruit and vegetable consumption in diverse community and laboratory settings. Due to the rapid rise in popularity within the scientific field, it is important to know if these devices will produce similar skin carotenoid scores within the same person and how these scores can be compared between devices in diverse populations. The data has been collected and being analyzed to calculate the absolute magnitude of difference and the intra class correlation between and among the devices. This research will inform the scientific community as to whether values from devices can be compared across studies and how these devices should be used in epidemiological studies of diet and health. ARS scientists in Grand Forks, North Dakota, are determining the differences in release of signaling molecules from fat cells (adipokines) and muscle cells (myokines) in exercise-trained and untrained adults following low- and high-intensity exercise. All samples have been collected and are being analyzed. This research will aid in determining how exercise-induced myokine and adipokine secretion influences the chronic low-grade inflammation that promotes cardiovascular and other diseases. ARS scientists in Grand Forks, North Dakota, are investigating how social modeling of eating behaviors, that is, how others eat and drink, impacts food choice and the amount consumed. This study focuses on understanding the role of social modeling on intake of dairy foods, an under consumed food group that provides essential nutrients in the American diet. To date, 72 of the 160 participants needed have completed the study. This study will fill a critical need for scientific evidence on the role that observing the eating and drinking habits of others affects the decision to consume a nutrient-dense food or beverage. ARS scientists in Grand Forks, North Dakota, are examining correlates and predictors of young adults’ eating habits, with particular emphasis on sociodemographics, reproductive health, and food upbringing. Emerging adulthood is a critical period of increasing autonomy during which key health behaviors are established; life course research finds food habits in early adulthood set individuals on lifelong nutrition trajectories, influencing food habits, preferences, and health outcomes for decades. Recruitment is expected to commence July 2024 and it is anticipated it will take about a month to collect all data. This study will provide essential information on young adults’ eating habits to assist in improving disparities in physical health in later adulthood. ARS scientists in Grand Forks, North Dakota, are investigating whether consuming an Indigenous diet produces non-targeted increases in physical activity and health of adult Great Plains Indians. Discussions with leadership of United Tribes Technical College (UTTC, Bismark, ND) led to a collaboration and agreement between the USDA-ARS Grand Forks Human Nutrition Research Center (GFHNRC) and faculty from UTTC and Sitting Bull College (Fort Yates, ND) to conduct the research. Working with UTTC, ARS scientist developed a healthy intervention diet comprised of Indigenous foods and recipes that were part of traditional food systems of the Great Northern Plains prior to the Indian Appropriations Act of 1851. Both UTTC and Sitting Bull collaborators worked alongside Dietary Core staff in Grand Forks, North Dakota, to prepare different recipes from the proposed menu, demonstrate hands-on skills for food preparation, and provide expertise on appearance and taste of Indigenous foods and recipes. The healthy Indigenous diet is undergoing sensory testing to identify final changes needed for seasoning, appearance, taste, and texture of the menu items. The protocol for the study including implementation of the dietary treatment and outcome measurements has been written and approved. Recruitment is expected to commence July 2024.

Accomplishments
1. Building sample healthy dietary patterns that include most of their energy from ultra-processed foods (UPF) according to the most common definition of UPF. The Dietary Guidelines Scientific Advisory Committee will investigate the relationship between UPF intake and cardiometabolic health outcomes for the first time for the 2025-2030 Dietary Guidelines for Americans (DGA). ARS scientists in Grand Forks, North Dakota, demonstrated that the most widely used definition of UPFs currently includes many nutrient-dense foods recommended in dietary guidance. They developed a sample menu that includes 91% of its energy from UPFs and still provides a nutrient-dense diet that aligns with DGA recommendations, scoring 86 out of 100 points for diet quality. This research is of great value to the nutrition science research community as it demonstrates that further refinement is needed to the definition of UPFs for it to be a usable framework to impact public health. Because this work emphasizes the importance of further research into this topic, it is also of value to policymakers, consumers, and the food industry, as evidenced by highlights on this research in popular media, invitations to present this work at plenary sessions in national and international scientific meetings and conferences, and several letters to the editor in response to the initial publication.

2. Development of a “research roadmap” on next steps needed by the scientific community to advance the research on ultra-processed foods (UPFs). Most of the research published to date on UPFs is observational, relies on disparate definitions of UPFs, and cannot be used to determine causation. An ARS scientist in Grand Forks, North Dakota, was invited to participate in a three-day intensive workshop and subsequent publication detailing the research necessary to continue advancing scientific understanding of UPFs and their potential impact on public health. This work identified 6 leading research questions that must be prioritized to deepen understanding of UPFs. The importance of this work is well-recognized by the scientific community and the food industry. A follow-up workshop was hosted in June 2024 with plans in progress to convene an additional workshop to monitor progress against the research roadmap objectives in coming years.

3. Defining healthy egg-free, dairy-free, pescatarian, and vegan diets that may be appropriate for consumption during lactation and modeling an “average” prenatal supplement. The 2020 Dietary Guidelines for Americans (DGA) describes a healthy vegetarian diet appropriate throughout the lifespan including lactation. But the DGA does not say how vegetarians who eat fish or who avoid eggs, dairy, or all animal foods can have a healthy diet. An ARS scientist in Grand Forks, North Dakota, developed models of different versions of the DGA vegetarian diet specifically for lactating mothers. The egg-free vegetarian version replaced eggs with beans, nuts/seeds, and soy products, and the dairy-free vegetarian version replaced all dairy foods with fortified soy milk and soy yogurt. The vegan diet replaced eggs and dairy in the same ways. The pescatarian diet included both eggs and dairy foods as well as fish. These vegetarian and pescatarian pattern variations were modeled with and without the inclusion of an average prenatal multivitamin and multimineral supplement, which most women continue to take throughout lactation. This research demonstrates that the vegetarian pattern in the 2020 DGA can be adapted for egg-free and dairy-free vegetarian diets as well as vegan and pescatarian diets and still meet most nutrition recommendations for adult women during lactation.

4. Chokeberry reduces inflammation in human preadipocytes. Chokeberry is an indigenous fruit from North America used as food and to prevent chronic disease by Indigenous peoples. Preadipocytes (precursors to fat cells) and mature adipocytes secrete inflammation markers. Chokeberries get their purple-red color from anthocyanins and anthocyanins are anti-inflammatory so this may be one way that chokeberries have prevented chronic disease. How chokeberries produce their anti-inflammatory effect is unknown but may happen in part by altering the epigenetic control of gene function. ARS researchers in Grand Forks, North Dakota, in collaboration with scientists from the University of North Dakota determined the anti-inflammatory effects of chokeberry extract and whether the effects occurred through an epigenetic mechanism in human primary preadipocytes studied in cell culture. The chokeberry extract was found to epigenetically reduced inflammation in the human preadipocyte cells. Thus, the health benefits that chokeberry may have had on Indigenous peoples in staving off chronic illness may be attributed to its anti-inflammatory effects. The epigenetic changes on inflammatory genes like IL-6 may maintain that protection between meals the include chokeberry. As a result, increased consumption of chokeberry juice may be a feasible dietary solution to reducing inflammation that can cause chronic disease.

5. Rethinking weight loss maintenance in humans. Models of appetite control have been largely based on negative feedback from gut and adipose (fat) signaling to central appetite centers. However, contemporary models posit that fat-free mass (FFM) or the energy demand of FFM (i.e., resting metabolic rate (RMR)) may play a primary role in the motivational drive for food intake (i.e., food reinforcement). The relative reinforcing value of food (RRVfood) is associated with energy intake (EI) and increases with an acute energy deficit. Chronic exercise-induced energy deficits lead to alterations in fat mass (FM), FFM, and RMR and provide an opportunity to test whether changes in FM, FFM, usual EI, or RMR are associated with RRVfood. ARS researchers in Grand Forks North Dakota, asked human participants to aerobic exercise expending 300 or 600 kcal, 5 d/wk for 12-wks and found that the reductions in RMR that occurred with weight loss were associated with increased food reinforcement as means of restoring FFM and RMR to pre-weight loss amounts. Contrary to current models, reductions in fat mass with weight loss were not associated with increased food reinforcement. Most people who lose weight gain back the original weight and additional weight. The results of this research provide novel data for understanding the maintenance of weight loss. Limiting reductions in RMR during weight loss may benefit weight maintenance by restricting increases in food reinforcement after weight loss.

6. Leisure-time bicycling among rural-living adults. Bicycling is a healthy form of physical activity that can be performed by most adults as part of leisure-time activity. However, little is known about increasing leisure-time bicycling of adults living in the rural areas of the United States. This study contrasted the prevalence and factors associated with leisure-time bicycling in adults living in urban settings with those living in rural settings. ARS researchers in Grand Forks, North Dakota, collaborated with scientists from several universities to analyze data from the 2019 Behavior Risk Factor Survey to determine the prevalence, demographic profile, and likelihood of meeting the physical activity guidelines of leisure time bicyclists. Adults living in urban counties compared to rural counties had a greater prevalence of leisure time bicycling (3.9% vs. 2.3%, respectively), with adults living in rural counties being 34% less likely to bicycle. Rural bicycling prevalence rates were lower across all demographics. Urban bicyclists, compared to rural bicyclists, cycled more months of the year. Overall, 85.5% of bicyclists met the aerobic physical guidelines, with no differences between urban and rural bicyclists. Bicycling is an important leisure time physical activity among adults in the U.S. However, the prevalence is lower for adults living in rural environments and the reasons for this disparity warrant further investigation.

Review Publications
Hess, J.M., Comeau, M.E., Fossum, D.L., Scheett, A.J. 2023. What exactly are “ultra-processed” foods? Can they be part of a healthy diet? ADCES in Practice. 1-4. https://doi.org/10.1177/2633559X231202795.
Brunelle, D.C., Larson, K.J., Bundy, A.N., Roemmich, J.N., Warne, D., Redvers, N. 2023. Chokeberry reduces inflammation in human preadipocytes. Journal of Functional Foods. 112:1-12. https://doi.org/10.1016/j.jff.2023.105947.
Lundquist, H., Slavin, J., Hess, J.M., Comeau, M.E. 2024. Cow’s milk as an important source of iodine for prenatal health and switching to plant-based milk can lead to iodine insufficiencies. Journal of Dairy Science Communications. 5(3):181-184. https://doi.org/10.3168/jdsc.2023-0424.
Hess, J.M., Comeau, M.E., Swanson, K., Burbank, M. 2023. Modeling ovo-vegetarian, lacto-vegetarian, pescatarian, and vegan USDA food patterns and assessing nutrient adequacy for lactation among adult females. Current Developments in Nutrition. 7(12):1-10. https://doi.org/10.1016/j.cdnut.2023.102034.
Hess, J.M., Comeau, M.E., Casperson, S.L., Slavin, J., Johnson, G.H., Messina, M., Raatz, S., Scheet, A.J., Bodensteiner, A., Palmer, D. 2023. Dietary guidelines meet NOVA: developing a menu for a healthy dietary pattern using ultra-processed foods. Journal of Nutrition. 153(8):2472-2481. https://doi.org/10.1016/j.tjnut.2023.06.028.
Pankey, C., Flack, K., Ufholz, K., Johnson, L., Roemmich, J.N. 2022. Influence of fat-free mass and resting metabolic rate on increased food reinforcement after exercise training. Sport Sciences for Health. 18:923–931. https://doi.org/10.1007/s11332-021-00876-y.
De Leon, A., Roemmich, J.N., Casperson, S.L. 2024. Daily dietary protein distribution does not influence changes in body composition during weight loss in women of reproductive years with overweight or obesity: a randomized controlled trial. Journal of Nutrition. 154(4):1347-1355. https://doi.org/10.1016/j.tjnut.2024.02.009.
Anderson, R., Casperson, S.L., Kho, H., Flack, K.D. 2023. The role of dietary protein in body weight regulation among active-duty military personnel during energy deficit: a systematic review. Nutrients. 15(18):1-15. https://doi.org/10.3390/nu15183948.
O'Connor, L.E., Higgins, K.A., Smiljanec, K., Bergia, R., Brown, A., Baer, D.J., Davis, C.D., Ferruzzi, M., Miller, K., Rowe, S., Rueda, J., Andres, A., Cash, S.B., Coupland, J., Crimmins, M., Fiecke, C., Forde, C.G., Fukagawa, N.K., Hall, K., Hamaker, B., Herrick, K.A., Hess, J.M., Heuven, L.A., Juul, F., Malcomson, F.C., Martinez-Steele, E., Mattes, R.D., Messina, M., Mitchell, A., Zhang, F. 2023. A research roadmap about processed foods, food processing, and human health in the context of the US food system: Proceedings from an interdisciplinary workshop. Advances in Nutrition. 14(16):1255-1269. https://doi.org/10.1016/j.advnut.2023.09.005.
Norman, A.C., Palmer, D.G., Moran, N.E., Roemmich, J.N., Casperson, S.L. 2024. Association of candidate single nucleotide polymorphism genotypes with plasma and skin carotenoid concentrations in adults provided a lycopene-rich juice. Journal of Nutrition. 154(7):1985-1993. https://doi.org/10.1016/j.tjnut.2024.05.022.