Research Project: Metabolism and Molecular Targets of Macro and Micro Food Components in the Development and Management of Obesity and Chronic Diseases

Location: Food Components and Health Laboratory

2018 Annual Report

Objectives
Diet is a modifiable factor that can influence the multitude of chronic health disorders that face the U.S. adult population, including type 2 diabetes, cardiovascular disease, some cancers, arthritis, endothelial dysfunction, and others. Through the experiments planned for this project, we will attempt to improve the understanding of the influence of diet on chronic disease. We will investigate direct effects of diet on cardiometabolic profile and additionally factors that influence weight gain, which increases risk for chronic disease. Objective 1. Determine the energy content of specific foods in the context of a mixed diet, and the absorption, metabolism and impact on biomarkers for health promotion of these foods or their macro and micro components. Objective 2. Determine the influence and interaction of the composition of food intake and exercise on glucoregulation, cardiometabolic profile, and metabolic flexibility (fuel management). Objective 3. Determine the extent to which the day-to-day variation in daily voluntary food intake, measured over at least 3 months, is related to diet composition, physical activity, and changes in physiological and metabolic markers related to energy balance, satiety and hunger.

Approach
Diet is a modifiable lifestyle factor that can influence the multitude of chronic diseases faced by an increasing proportion of the U.S. population, including type 2 diabetes, hypertension, vascular dysfunction, cardiovascular disease, cancer, and arthritis. Moreover, the widespread global prevalence of these diseases threatens the quality of life and places additional stresses on an already overburdened health care system. This project, through highly controlled human feeding studies, will target specific factors which influence risk for and development of chronic disease. First, research will be conducted to improve accuracy of the energy value of foods, which can impact weight gain, a risk factor for chronic disease. Second, research will be conducted to investigate dietary factors that can influence cardiometabolic profile, i.e. risk for cardiovascular disease, stroke, or diabetes. Third, we will study how diet influences voluntary food intake, again impacting weight gain, a risk factor for chronic disease. The outcomes of this research will provide a better understanding of 1) the energy content of specific foods in the context of a mixed diet, and the absorption, metabolism and impact on biomarkers for health promotion of these foods or their components, 2) dietary and lifestyle influences on diabetes and cardiovascular disease risk, and 3) the extent to which the day-to-day variation in daily voluntary food intake is related to diet composition. This research will fill knowledge gaps in the metabolism of macro and micro food components related to the development and management of obesity and chronic diseases, and provide a scientific basis for dietary recommendations and nutrition policy.

Progress Report
Progress was made for both objectives of this project plan linked to National Program 107 Plan, focusing on Component 3 to provide a Scientific Basis for Dietary Guidance. Progress has been made addressing Problem Statement 3B: Identify Roles of Food, Food Components and Physical Activity in Promoting Health and Preventing Disease through studies on tree nuts and berries investigating energy metabolism, sugar metabolism, and factors related to risk for cardiovascular disease. Under Objective 1, a large study was completed focusing on the effect of cashew nut consumption on biomarkers for cardiovascular disease. This work builds on the other research conducted in previous years on measuring the energy value of tree nuts (calories in a serving), determining how processing (roasting, chopping and making nut butter) affects the breakdown of nuts, and other health benefits from tree nut consumption. The U.S. Food and Drug Administration stated in a qualified health claim that consumption of most nuts may reduce the risk of heart disease. Cashew nuts are explicitly excluded from this health claim due to their content of saturated fats. Several studies have been conducted to test the effect of cashew nuts on blood lipids, and these studies have produced conflicting results. A dietary intervention study was conducted to determine the effect of cashew nuts fed at the amount specified in the health claim on risk factors (cholesterol, blood pressure, inflammatory markers) for cardiovascular disease. Consumption of 1.5 servings (42 g) of cashew nuts per day, the amount associated with the FDA qualified health claim for tree nuts and cardiovascular disease, did not positively or adversely affect any of the primary risk factors for cardiovascular disease. Under Objective 2, one human study was completed and a second human study is ongoing. Because two-thirds of Americans are classified as overweight or obese, these individuals are at an increased risk for cardiovascular disease, diabetes, cancer, and other morbidities. Lifestyle modification remains an attractive strategy for combating obesity, as dietary approaches offer solutions to weight loss and improved health without negative side effects. Anthocyanins, a class of red, blue, and purple hues in plants, are one of the main classes of compounds gaining substantial attention in regard to obesity. Studies have found that rodents consuming a high fat diet gain less weight when also consuming these colorful pigments. A feeding study was conducted in which men consumed blackberries every day for a week. Indirect calorimetry was used to determine how many calories they were burning, and also their ratio of carbohydrate to fat burning. In this study, blackberries increased fat burning (oxidation). A second larger study of men and women is ongoing. This second study also includes dietary treatments to help identify which components of berries (fiber or anthocyanins) may be responsible for their observed metabolic effects. Under Objective 3, one study was completed. Weight gain is caused by an imbalance between food intake and energy expenditure. When food intake exceeds energy expenditure, the extra energy is stored as fat, leading to obesity. Amount of food consumed is driven by many complex factors beyond appetite. One factor that may help control food intake is the inclusion of satiating foods in the diet. While perceived by many as “high calorie” foods, nuts are actually associated with increased satiety, reduced food intake, and decreased body weight. Several studies have suggested that nut intake can reduce hunger and increase fullness ratings after a meal and snacking on nuts can reduce energy consumed during follow-up meals. Thus, inclusion of nuts in the diet may assist in body weight control. A study was completed to determine if consumption of mixed nuts influences food intake and choice. Included in this study were measures to determine how personality characteristics affect food choice, including mood, stress, tendency to seek approval, tendency to avoid criticism, tendency toward food cravings, and approach to food intake control.

Accomplishments
1. Walnut consumption lowers fecal concentration of bile acids. Bile acids are compounds associated with risk of cancer, and secondary bile acids are produced by microbiota in the human colon. These compounds can have local effects on cellular metabolism and have been associated with increased risk for colorectal cancer. They can also be absorbed into circulation and have effects on systemic cellular regulation. ARS researchers at the Beltsville Human Nutrition Research Center, Beltsville, Maryland, conducted a study to determine how walnut consumption affects the concentration of fecal secondary bile acids. When walnuts were in the diet, the concentration of secondary bile acids was reduced from 40 to 50%, possibly reducing colorectal cancer risk.

2. Body core temperature can be used to estimate calories burned. Measuring the amount of calories burned by people may provide a means of monitoring and reducing obesity, estimating nutritional requirements, reducing obesity, maintaining energy balance during athletics, and modeling human body temperature responses. However, measuring the rate of calories burned is challenging as the equipment required can limit the type and intensity of activity during measurement. ARS researchers at the Beltsville Human Nutrition Research Center, Beltsville, Maryland, developed a model to predict metabolic rate from core body temperature. This model will be useful for military and nonmilitary applications, including field studies or other circumstances where direct measurements of calories burned are impractical.

Review Publications
Mandalari, G., Parker, M.L., Grundy, M.M., Grassby, T., Smeriglio, A., Bisignano, C., Raciti, R., Trombetta, D., Baer, D.J., Wilde, P.J. 2018. Understanding the effect of particle size and processing on almond lipid bioaccessibility through microstructural analysis: from mastication to faecal collection. Nutrients. 10. https://doi.org/10.3390/nu10020213.
Holscher, H.D., Taylor, A.M., Swanson, K.S., Novotny, J., Baer, D.J. 2018. Almond consumption and processing affects the composition of the gastrointestinal microbiota of healthy adult men and women: a randomized controlled trial. Nutrients. 10. https://doi.org/10.3390/nu10020126.
Welles, A., Buller, M.J., Looney, D.P., Rumpler, W.V., Gribok, A.V., Hoyt, R.W. 2018. Estimation of metabolic energy expenditure from core temperature using a human thermoregulatory model. Journal of Thermal Biology. 72:44-52. https://doi.org/10.1016/j.jtherbio.2017.12.007.
Fitzgerald, K.C., Vizthum, D., Henry-Barron, B., Schweitzer, A., Cassard, S.D., Kossoff, E., Hartman, A.L., Kapogiannis, D., Sullivan, P.J., Baer, D.J., Mattson, M., Appel, L.J., Mowry, E.M. 2018. Effect of intermittent versus daily calorie restriction on changes in weight and patient reported outcomes in people with multiple sclerosis. Journal of Multiple Sclerosis and Related Disorders. 23:33-39. https://doi.org/10.1016/j.msard.2018.05.002.
Holscher, H.D., Guetterman, H.M., Swanson, K.S., An, R., Matthan, N., Lichtenstein, A., Novotny Dura, J., Baer, D.J. 2018. Walnut consumption alters the gastrointestinal microbiota, microbially derived secondary bile acids, and health markers in healthy adults: a randomized controlled trial. Journal of Nutrition. 148:861-867. https://doi.org/10.1093/jn/nxy004.
Mahabir, S., Pfeiffer, R., Xu, X., Baer, D.J., Taylor, P.R. 2017. Effects of low-to-moderate alcohol supplementation on urinary estrogen metabolites in postmenopausal women in a controlled feeding study. Cancer Medicine. 6:2419-2423. https://doi.org/10.1002/cam4.1153.
Park, Y., Dodd, K., Kipnis, V., Thompson, F.E., Potischman, N., Schoeller, D.A., Baer, D.J., Midthune, D., Troiano, R., Bowles, H., Subar, A.F. 2018. Comparison of self-reported dietary intakes from the Automated Self-Administered 24-h recall, 4-d food records, and food-frequency questionnaires against recovery biomarkers. American Journal of Clinical Nutrition. 107:80-93. https://doi.org/10.1093/ajcn/nqx002.
Liska, D.J., Cook, C.M., Wang, D., Gaine, P., Baer, D.J. 2016. Trans fatty acids and cholesterol levels: an evidence map of the available science. Food and Chemical Toxicology. 98(B):269-281. https://doi.org/10.1016/j.fct.2016.07.002.
Gribok, A., Leger, J., Stevens, M., Hoyt, R., Buller, M., Rumpler, W.V. 2016. Measuring the short-term substrate utilization response to high-carbohydrate and high-fat meals in the whole-body indirect calorimeter. Physiological Reports. 4. https://doi.org/10.14814/phy2.12835.
Gribok, A., Rumpler, W.V., Dipietro, L. 2016. Kinetics of post-exercise excess CO2 production and substrate oxidation in two dysglycemic and euglycemic older women a case study. Diabetes Case Reports. 1. https://doi.org/10.4172/2572-5629.1000107.