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ARS Home » Plains Area » Grand Forks, North Dakota » Grand Forks Human Nutrition Research Center » Healthy Body Weight Research » Research » Research Project #435947

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

Location: Healthy Body Weight Research

2023 Annual Report

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.

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
Progress was made on all four objectives. Software was developed in-house that will be used to test and train executive function in individuals with overweight or obesity. Executive function is a set of mental processes that you use every day to make decisions – such as what kinds of foods you choose to eat and when and where you eat those foods. The goal of this newly developed executive function training program, titled ‘EFfect-food choices’, is 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. The ‘EFfect-food choices’ training program has been developed and all approvals needed to conduct a human study completely online have been obtained. Beta testing of the ‘EFfect-food choices’ training program will be concluded in July 2023 and subject recruitment is expected to commence August 2023. ARS scientist 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 have received 1283 beef samples and are currently processing the samples for analyses of fatty acid and amino acid content. 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, tested the efficacy of two patterns of daily protein intake to promote healthy changes in body composition and dietary adherence during weight loss in overweight and obese women of childbearing age. For one group, daily protein is evenly distributed among breakfast, lunch, and dinner (30 g at each meal). For the other group, dietary protein distribution represents a typical protein eating pattern in which the majority of protein is consumed with the evening meal (10g at breakfast, 15g at lunch, 65g at dinner). We found no effect of protein distribution on changes in body composition or cardiometabolic risk factors beyond those observed as a result of weight loss. But evenly distributing dietary protein throughout the day resulted in women being less distracted or bothered by hunger and feeling less deprived. Evenly distributing protein throughout the day also lessened the relative reinforcing value of energy-dense foods. These results demonstrate that evenly distributing protein intake throughout the day may improve a woman’s ability to stay “on track” with her weight control behaviors and goals. ARS scientists in Grand Forks, North Dakota, are investigating the effects of two patterns of daily protein intake on energy metabolism and fat oxidation in healthy weight individuals. For one group, daily protein is evenly distributed among breakfast, lunch, and dinner (30 g at each meal). For the other group, dietary protein distribution represents a typical protein eating pattern in which the majority of protein is consumed with the evening meal (10g at breakfast, 15g at lunch, 65g at dinner). To date, 18 participants have completed the study and recruitment has begun for the remaining 2 participants needed to complete the study. 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. To date, one more exercised-trained participant is needed to complete the study. 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. 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. The study has been approved by the University of North Dakota Institutional Review Board and subject recruitment has begun. 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. This study will provide essential information on young adults’ eating habits to assist in improving disparities in physical health in later adulthood.

1. Defining healthy egg-free, pescatarian, and “pescavegan” vegan diets. The 2020 Dietary Guidelines for Americans (DGA) describes a healthy vegetarian diet. But the DGA does not say how vegetarians who do not eat eggs can have a healthy diet or how vegetarians or vegans who eat fish can have a healthy diet. An ARS scientist in Grand Forks, North Dakota, tested different versions of the DGA vegetarian diet. The egg-free vegetarian version replaced eggs with beans, nuts/seeds, and soy products. The “pescavegan” diet also replaced dairy foods with soy milk and soy yogurt and added fish. The pescatarian diet included both eggs and dairy foods as well as fish. These vegetarian and pescatarian patterns provided enough nutrients for most Americans. However, there was not enough iron in the egg-free vegetarian or pescatarian patterns for females between 19 and 50 years of age, and the “pescavegan” pattern did not provide enough zinc for males over the age of 50. The vegetarian pattern in the 2020 DGA can be adapted for egg-free vegetarian, pescatarian, and “pescavegan” diets and still meet nutrition recommendations for most healthy adults.

2. Technological advances to noninvasively determine changes in vegetable consumption. Much research has been devoted to getting people to eat more fruits and vegetables (FV). But accurately assessing changes in FV consumption is difficult. Carotenoids (what gives plants their bright yellow, orange, and red color) are a biomarker of FV consumption that circulate in the blood and are deposited in the skin. But measuring carotenoids has historically required technical expertise and complex instrumentation. Recent technological advances have produced relatively simple analyzers that use pressure-mediated reflection spectroscopy (RS) to measure skin carotenoid levels. These compact, portable devices are ideal to noninvasively assess FV consumption, especially in challenging populations (e.g., young children, elderly), but the sensitivity of this technology to detect changes in FV consumption was not known. ARS scientists in Grand Forks, North Dakota, tested the capacity of this technology to detect changes in skin carotenoids in response to different amounts of carotenoids intake. Healthy adults drank either water or three different amounts of vegetable juice (0.8 cups, 1.5 cups, or 2 cups) every day for 8 weeks and skin carotenoids levels were measured weekly. We found that RS can detect changes in the consumption of carotenoid rich FV, but that the amount consumed and how long the FV are consumed are important factors that need to be considered when using this technology. The results from this research provide essential knowledge on the utility of RS to noninvasively determine carotenoid intake when applied in interventional or epidemiological research.

3. Source of information on trust of pulse nutrition information and perceived likelihood of following dietary guidance. Most Americans have nutritionally inadequate diets, eating too few fruits and vegetables and too much salt and sugar relative to the recommendations outlined by the Dietary Guidelines for Americans. While there are many barriers to healthy eating, lack of trust in dietary guidance sources is relatively understudied. ARS scientists in Grand Forks, North Dakota, tested whether the source of diet information and guidance impacts perceptions of the information and perceived likelihood of following the guidance. USDA and hospital sources were perceived as more accurate, trustworthy, reliable, and more desirable to learn more from relative to social media. However, there were no differences in the likelihood of following guidance depending on source, suggesting that trust in the source of information does not influence perceived likelihood of following dietary recommendations for pulses.

Review Publications
Casperson, S.L., Scheett, A., Palmer, D.G., Jahns, L., Hess, J.M., Roemmich, J.N. 2023. Biochemical validation of a self-administered carotenoid intake screener to assess carotenoid intake in non-obese adults. Current Developments in Nutrition. 7(2):1-10.
Hess, J.M., Comeau, M.E. 2023. Modeling lacto-vegetarian, pescatarian, and 'pescavegan' USDA Food patterns and assessing nutrient adequacy for healthy, non-pregnant, non-lactating adults. Frontiers in Nutrition. 10. Article 113792.
Casperson, S.L., Jahns, L.A., Larson, K.J., Hess, J.M., Palmer, D., Roemmich, J.N. 2023. Sensitivity of pressure-mediated reflection spectroscopy to detect dose-dependent changes in skin carotenoids: A randomized controlled trial. Journal of Nutrition. 153(2):588-597.
Hess, J.M., Comeau, M.E. 2022. Application of dairy-free vegetarian and vegan USDA Food Pattern Models for non-pregnant, non-lactating healthy adults. Journal of Food Science.
Cifelli, C.J., Fulgoni, K., Fulgoni, V.L., Hess, J.M. 2022. Disparity in dairy servings intake by ethnicity and age in NHANES 2015-2018. Current Developments in Nutrition. 7(2). Article 100010.
Hess, J.M. 2022. Understanding the link between frequency of eating and cardiometabolic health outcomes in Americans who "snack". Journal of Dairy Science Communications. 3(6):462-466.
Larson, K.J., Singh, B., Bundy, A.N., Brunelle, D., Bukowski, M.R., Roemmich, J.N. 2023. Effects of maternal HF diet and absence of TRPC1 gene on mouse placental growth and fetal intrauterine growth retardation (IUGR). Journal of Nutritional Biochemistry. 114. Article 109162.