Obesity clinical trials at UC Davis
10 research studies open to eligible people
open to eligible people ages 20-45
The purpose of this research is to investigate whether consuming two different kinds of olive oil will change risk factors related to cardiovascular disease, including levels of good and bad cholesterol, levels of inflammation, and levels of gene expression.
open to eligible females ages 18-45
This study is designed to compare two types of snacks (almonds or a cereal-based snack), eaten between meals, on measures of appetite, including appetitive hormones, self-reported feelings of hunger and fullness, and food intake at a buffet meal or in the home environment. The investigators hypothesize that the acute responses of appetitive hormones to a meal challenge protocol will differ between almond and cereal-based snacks based on multivariate models of satiety that will be predictive of ad libitum food intake at a dinner meal as part of the meal challenge protocol. Further, the investigators will estimate if, under free-living conditions, self-selected and self-reported food intake will show appropriate energy compensation for the added calories of the snacks, and determine if one type of snack is superior to the other in this regard.
open to eligible females ages 35-65
Patients undergoing Bariatric Surgery at the University of California Davis Medical Center will be divided into two groups, one receiving Standard of Care pain control medications vs the second group which will receive non-narcotic pain medications with rescue pain medications available if needed
A Study of the Effects of Sweet Cherry Juice on Metabolism (converting food to energy) and Heart Health
open to eligible people ages 20-65
This study aims to determine the effects of consuming sweet cherry juice on cardiovascular function, glucose regulation, and lipid status in overweight human subjects. The investigators hypothesize that sweet cherry juice consumption will improve metabolic and physiological status in overweight persons compared to a placebo.
Metabolic and Bio-Behavioral Effects of Following Recommendations in the Dietary Guidelines for Americans
open to eligible females ages 35-64
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.)
“What are the effects of consuming sugar- and aspartame-sweetened beverages with standardized diets?”
open to eligible people ages 18-40
It is not known whether consumption of excessive amounts of sugar can increase risk factors for cardiovascular disease or diabetes in the absence of increased food (caloric) intake and weight gain, nor whether the negative effects of sugar consumption are made worse when accompanied by weight gain. This study will investigate the effects of excess sugar when consumed with an energy-balanced diet that prevents weight gain, and the effects of excess sugar when consumed with a diet that can cause weight gain. The results will determine whether excess sugar consumption and excess caloric intake that lead to weight gain have independent and additive effects on risk factors for cardiovascular disease or diabetes, and will have the potential to influence dietary guidelines and public health policy.
Davis, California and other locations
“Using tissue samples to better understand the metabolism and genetics of obesity”
open to eligible people ages 18-65
Research the genetic and biomechanical markers of human adipose tissue on patients with morbid obesity. Additional tissue/fluid collection is also gathered during the time of surgery.
The Influence of Honey-flavored Yogurt on Low-grade Inflammation and Gut Health in Middle to Older Aged Women
open to eligible females ages 45-65
A randomized, double-blind, crossover dietary intervention trial will test the effects of 4 weeks of daily honey-flavored yogurt intake on markers of inflammation (Th17 cytokines) and oxidative stress (NOX2, UA, RSNO) and associative changes with microbial derived metabolites (SCFAs, BAs, ellagitannins), metabolism and the fecal microbiome. The above suite of selected markers will capture diet-induced systemic changes in inflammation and oxidative stress, while assessing associated microbial changes.
The Walnut Study: Measuring the Changes in Gut Microbiota (bacteria) and Cardiometabolic Biomarkers (cholesterol)
open to eligible people ages 20-65
The researchers will investigate blood and fecal responses in qualified study participants after eating walnuts for 4 weeks compared to not eating walnuts for 4 weeks. The two dietary interventions will be separated by a 4 week washout period. The order of diets will be random; study participants will complete both interventions. Dietary modifications will be part of the study protocol.
“Postmenopausal Women Needed for a Research Study”
open to eligible females ages 45-65
This study seeks to confirm and extend previous finding that four weeks of daily intake of 40 g of walnuts improve microvascular function, increasing the reactive hyperemia index (RHI), effects which were greatest in individuals with the worst initial RHI and correlating to circulating levels of vasoactive plasma epoxides. The current trial will enroll postmenopausal women who are at risk for cardiovascular disease due to their menopausal status and increased central adiposity. The initial trial focused on non-esterified (i.e. plasma) derived oxylipins, but substantial and unique changes were also observed in the esterified lipoprotein pool. The current study will add the esterified lipoprotein pool, important, as the mechanisms by which walnut intake influences endothelial function are currently undefined, but may include lipoprotein induced modulation of vascular hemostasis. As a secondary objective, primary metabolism and urolithin metabotype will be analyzed as a way to capture the influence of potential differences in habitual diet and metabolism on physiologic response. Therefore, this study will combine measures of cardiovascular physiology, metabolomics, and walnut-derived metabolite analyses to assess the 12 week influence of 40 g of daily walnut intake on the health of overweight and obese postmenopausal women.