Research Project: Strategies to Alter Dietary Food Components and Their Effects on Food Choice and Health-Related Outcomes

Location: Food Components and Health Laboratory

2023 Annual Report

Objectives
Objective 1: Determine how changes in dietary food components macro and micronutrients composition affect taste, palatability, food choice and health. Objective 2: Investigate the effect of food processing methods on nutrient intake and disease risk reduction. Objective 3: Determine how foods and food components alter food and energy intake (measured over 2 months).

Approach
United States (U.S.) agriculture produces a bountiful array of healthful foods to support the nutritional needs of the American population, providing us vast options to use diet to support health and reduce risk of chronic disease. However, healthful foods are useless if they are not selected for consumption. The U.S. Department of Agriculture’s (USDA) What We Eat in America dietary survey has demonstrated that Americans are not following the Dietary Guidelines, but rather are eating too much salt, sugar, and protein, and falling short on fruits and vegetables. A complex array of factors influences food selection and consumption, including taste/palatability, satiety, convenience, healthfulness, and emotional/psychological factors. This project plan aims to improve understanding of these drivers of food intake and health consequences of consuming certain foods of concern. We will conduct two human feeding interventions to target different factors influencing food selection and consumption. In one study, we will investigate different methods for altering food preference, through either gradual or rapid alterations in the diet. In another study, we will provide a satiating food item twice per day, then measure all other food selected and consumed. We will also evaluate emotional and psychological factors throughout the food selection study. Finally, recognizing that consumers struggle with the balance between convenience and healthfulness, we will evaluate health effects of raw vs. processed meat, to see whether selection of this processed convenience food has negative health consequences. This research will offer paradigms for approaches to improve dietary choices by Americans, and provide a scientific basis for dietary recommendations and nutrition policy.

Progress Report
This report is for project 8040-51530-011-000D entitled "Strategies to Alter Dietary Food Components and Their Effects on Food Choice and Health-Related Outcomes" which contributes to National Program 107, focusing on Component 1 Linking Agricultural Practices and Beneficial Health Outcomes, Component 3 (Scientific Basis for Dietary Guidance), and Component 4 (Prevention of Obesity and Obesity-Related Diseases) through human studies investigating food choice, food intake regulation, taste, and factors related to risk for cardiovascular disease, diabetes, and obesity. For Objective 1, research protocols were finalized for a study to determine the most effective approach to reduce the amount of dietary added sugar in order to best modulate the perception of sweetness. Recipes and menus were developed, and foods were developed and tested for use in this study. Recruitment of volunteers for this study was initiated and completed. The dietary intervention component of this research was initiated. Also, in support of this objective, an overview of reviews on the association of low calories sweeteners consumption with body weight and adiposity was conducted to highlight how different populations, intervention/exposures, comparators, and study designs produce varying conclusions regarding the efficacy of low calories sweeteners for body weight management. This project was initiated since systematic reviews investigating the effect of low calories sweeteners on body weight implement different approaches, methodologies and criteria to answer the same research question; these yield disparate results and conclusions. For Objective 2, a research protocol was completed to evaluate the health consequences of consuming minimally processed or further processed meat. Recipe and menu development were completed, volunteers were recruited, and the intervention was conducted. All biospecimens were collected and analyses was initiated. Also in support of Objective 2, the lab organized a workshop (funded by National Institute for Food and Agriculture) to convene experts in nutrition, food science, and epidemiology from government, academia, and industry in order to develop a Research Roadmap to identify priorities for investigating effects of processed foods intake on obesity and cardiometabolic diseases in the U.S. A manuscript outlining the research roadmap is currently under review. For Objective 3, a study was planned and approved, and data were collected investigating how dietary components can influence voluntary food intake. For this initial study, volunteers were provided mixed nuts during one treatment period and provided no additional food during a second treatment period (as part of a randomized crossover study design). In addition to the mixed nuts that had to be consumed, research volunteers are free to choose all of the other foods they wanted to consume each day for 3 weeks (per treatment). Research volunteers could choose the specific foods and any amount. The amount consumed of each food selected was measured. Data analyses are ongoing and focus on how nuts might affect the total amount of food selected and shifts in dietary patterns.

Accomplishments
1. Dietary sweetness is not associated with body weight. Some governmental and health organizations provide dietary guidance to avoid dietary sweetness, regardless of dietary source, in order to reduce risk of obesity. ARS researchers at the Beltsville Human Nutrition Research Center, Beltsville, Maryland, conducted a scoping review and evidence map to characterize the research that investigated associations between dietary sweetness and body weight. Although there is evidence from studies that have investigated associations between intakes of sweet foods and beverages, sugars, and sweeteners and body weight, there is a limited depth of evidence on the association between total dietary sweetness and body weight. These findings will inform U.S. dietary guidance.

Review Publications
Gebauer, S.K., Baer, D.J. 2022. Trans-fatty acids: health effects, recommendations, and regulations. Encyclopedia of Human Nutrition. 2013:288-292. https://doi.org/10.1016/B978-0-12-375083-9.00102-1.
Fitzgerald, K.C., Bhargava, P., Smith, M.D., Vizthum, D., Henry-Barron, B., Cassard, S.D., Kapogiannis, D., Baer, D.J., Sullivan, P.J., Calabresi, P.A., Mowry, E.M. 2022. Intermittent calorie restriction alters T cell subsets and metabolic markers in people with multiple sclerosis. EBioMedicine. 82:1-13. https://doi.org/10.1016/j.ebiom.2022.104124.
Higgins, K.A., Rawal, R., Baer, D.J., O'Connor, L.E., Appleton, K.M. 2022. Scoping review and evidence map on the relation between exposure to dietary sweetness and body weight-related outcomes in adults. Advances in Nutrition. 13(6):2341-2356. https://doi.org/10.1093/advances/nmac090.