Obesity Clinical Trials

This study, at the Western Human Nutrition Research Center (WHNRC), will focus on whether or not achieving and maintaining a healthy body weight is the most important health promoting recommendation of the Dietary Guidelines for Americans (DGA).The investigators hypothesize that improvement in cardiometabolic risk factors resulting from eating a DGA style diet will be greater in people whose energy intake is restricted to result in weight loss compared to those who maintain their weight. The investigators further propose that during a state of energy restriction, a higher nutrient quality diet such as the DGA style diet pattern, will result in greater improvement in cardiometabolic risk factors compared to a typical American diet (TAD) pattern that tends to be lower nutrient quality (more energy-dense and less nutrient-rich.) Read Less

The purpose of this study is to conduct a micro-randomized trial to learn which evidence-based targets within a mobile intervention for binge eating and weight-related behaviors are most impactful for which people and in what sequence. Read Less

African American adults sleep less and obtain worse quality sleep compared to the national average, and emerging evidence links inadequate sleep with greater morbidity and mortality from chronic diseases such as diabetes, obesity, and cancer. To address this public health concern, the proposed research seeks to use a multi-method approach to adapt a sleep intervention for African American adults with overweight/obesity not meeting national sleep duration or physical activity recommendations. The overall goal of the project is to reduce cancer and obesity-related health disparities among African Americans. Read Less

The major objective of this project is to examine whether daily consumption of milk polar lipids (MPLs) influences cardiometabolic risk factors. Read Less

Americans commonly consume excess amounts of dietary fructose. Added fructose has been shown to have an adverse impact on metabolic health, including increased insulin resistance and type 2 diabetes (T2D) risk. However, the mechanisms that link dietary fructose and metabolic health are poorly understood. Malabsorption or incomplete metabolism of fructose in the small intestine is common in the population. Excess fructose reaches the colon where it may change the structure and function of the gut microbiome, alter bacterial metabolites and trigger inflammatory responses impacting T2D risk. To elucidate whether commonly consumed levels of dietary fructose influence metabolic outcomes through altering the gut microbiome, the research team will randomize 30 participants to a controlled cross-over dietary intervention, in which the participants will consume 12-day isocaloric, added fructose or glucose diets (25% of total calories) separated by a 10-day controlled diet washout period. The research team aims to: 1. Determine the relationships between high fructose consumption, the gut microbiome and metabolic risk. 2. Characterize the causal role(s) that fructose-induced alterations to the gut microbiome have on metabolic risk using a germ-free mouse model. The research team will measure 1) microbiota community structure and function via metagenomic sequencing of stool, 2) fecal metabolites via targeted and untargeted metabolomics, 3) anthropometrics, 4) insulin resistance, serum markers of T2D risk and inflammatory cytokines, 5) fecal microbial carbohydrate oxidation capacity and 6) liver fat via MRI elastography. The research team will use novel statistical approaches, including Distributed Lag Modeling, to understand the complex relationships between diet, the microbiome, metabolites and health outcomes. The research team will then conduct controlled dietary interventions and fecal microbiome transplantation studies in germ-free mice. Donor fecal samples from human participants in both the glucose and fructose arms of the clinical intervention will be transplanted into germ-free and colonized mice to establish a causal relationship between fructose-induced changes to the gut microbiome, liver fat and metabolic and inflammatory changes known to increase risk for T2D. The research team aims to comprehensively assess the structural and functional changes to the gut microbiome brought about by a high fructose diet. Determining the impact of excess fructose on the microbiome will help identify novel means by which fructose contributes to metabolic disease risk. In addition to identifying strategies to improve metabolic health in adults, data from this proposal could help inform targeted approaches to mitigate future disease risk in vulnerable populations that consume high levels of fructose, such as children. Read Less

The study is testing a new study medicine to treat people living with overweight or obesity. The aim of this study is to see if the medicine is safe, how it works in your body, and what your body does to the study medicine. Participants will either get the study medicine or placebo (a "dummy medicine" similar to the study medicine but without active ingredients) given as an injection under your skin. Which treatment the participants get is decided by chance. The study medicine is a potential new medicine which cannot be prescribed by doctors. Read Less

In addition to chronically elevated MSNA, there is a growing recognition that hypertension in states of insulin resistance and obesity may also be attributed to an increased vascular sensitivity to MSNA (1, 2, 13, 36-38). To study this phenomenon, we quantify vascular sensitivity to MSNA using an innovative, moment-to-moment assessment of the blood pressure response following individual bursts of muscle sympathetic nerve activity (MSNA), (10, 11, 34, 37). This approach is termed 'sympathetic-vascular transduction (SVT).' We will examine the hypothesis that SVT is exaggerated in obesity and insulin resistance and is attenuated by suppression of oxidative stress. Oxidative stress is the overabundance of reactive oxygen species and is another hallmark of hypertension, obesity, and insulin resistance. Oxidative stress can be safely reduced via intravenous infusion of ascorbic acid (Vit C) (4, 28). Therefore, we will use a randomized, double-blinded, placebo-controlled approach to test the hypothesis that elevated SVT will be attenuated by suppression of oxidative stress via ascorbic acid I.V. infusion compared with saline I.V. infusion (placebo) in obese adults with insulin resistance. Our study will identify a unique mechanism that can be targeted to reduce the excessively high prevalence of hypertension and risk for CVD in obesity and insulin resistance. Read Less

This study is a pilot open label crossover trial to assess the feasibility and acceptability of reducing ultra- processed foods (UPF) in a personalized manner from the diets of patients with major depressive disorder who eat a large percentage of UPF. Read Less

The purpose of the present pilot is to evaluate the outcomes of adding a patient coach to support the Optimal Health Weight and Lifestyle (OHWL) Clinic plan developed by PI Dewar, specifically to address barriers and facilitators of adherence to the plan. This will be accomplished via a coach who is not embedded in clinic care and is supported by pilot research funds. Evaluation of the coach activities, conducted by research personnel, will include compiling data from the electronic health record, a short set of patient report and performance measures, and qualitative interviews. Read Less

The purpose of this study is to determine the effectiveness of mobile health applications in improving health outcomes and the subsequent benefit of improving type II diabetes outcomes in a low socioeconomic Hispanic population. This study will involve a 6-month long commitment where participants will be expected to weigh themselves every morning, at the same time, and check their blood glucose readings daily before and after meals for at least three meals in the day. Read Less

The purpose of this study is to determine the effectiveness of mobile health applications in improving health outcomes and type II diabetes outcomes in type 2 diabetics. This study will involve a 6-month long commitment where participants will be expected to weigh themselves every morning, at the same time, and check their blood glucose readings daily before and after meals for at least three meals in the day. Read Less

This trial studies how well nutrition and exercise interventions work in reducing androgen deprivation therapy-induced obese frailty in prostate cancer survivors. Individualized nutrition and exercise advice for prostate cancer patients on androgen deprivation therapy may help to reduce obese frailty and change the levels of myokines in blood. Read Less