Clinical Research Directory

Effects of Acute Sleep Deprivation on Human Behaviours

This study will investigate whether acute sleep deprivation affects appetite, eating behavior, and physical activity in both regular exercisers and physically inactive individuals.

Metabolic Effects of Short-term Ultra-processed Food Intake (MEST-UPF)

The overall aim of this project is to study the effects of short-term high ultra-processed food intake, compared to nutrient- and energy density matched low ultra-processed food (UPF) intake, on energy intake and appetite. A total of 24 men and women who meet all inclusion criteria and none of the exclusion criteria will be invited to participate. A randomized 2\*2 factorial four-way crossover study will be conducted at the Department of Internal medicine and Clinical Nutrition at the University of Gothenburg, comparing a high-UPF meal to a low-UPF meal also with high and/or low energy density. A supervised breakfast meal will be served, and postprandial blood samples and appetite measures will be collected continuously up to 4 hours after the breakfast meal. Subsequently, an ad libitum lunch meal will be served, and energy intake will be recorded.

Interaction Between White Potato Consumption and Meal Timing on Glycemic Response and Appetite in Adults

The purpose of this study is to evaluate the interaction between white potato consumption and meal timing on glycemic response, subjective appetite, and energy intake in adults. The investigators hypothesize that white potatoes will modulate glycemic response, enhance satiety, and mitigate subsequent meal consumption and overall food intake when compared with meals containing low glycemic carbohydrates. Furthermore, they anticipate that the timing of white potato consumption will yield differential effects, with breakfast consumption exerting a more pronounced impact on satiety and subsequent food intake reduction compared to dinner consumption.

Effects of a Collagen Supplement on Quality of Life, Appetite and Glycaemic Control

This is a clinical trial aimed to investigate if a collagen supplement can improve quality of life, appetite and blood sugar in overweight and obese adults aged 18-65. Hypothesis: Consumption of a collagen supplement for 8 days will improve quality of life and improve glycaemic control in comparison with a placebo in individuals overweight or with obesity with a perceived low quality of life. Participants will be asked to: 1. Consume a collagen peptide supplement for a total of 8 days at a time 2. Fill in questionnaires about quality of life, appetite, mood and energy 3. Wear continuous glucose monitors

Hypoxia, Appetite, and Energy Intake in Young Female Adults

The goal of this clinical trial is to investigate the effects of acute passive continuous hypoxemia (simulated high-altitude at rest) on appetite and energy intake in healthy young female adults. The main questions it aims to answer are: * Does six hours of simulated high-altitude (5000 meters) reduce scores of subjective appetite and energy intake? * Do changes in appetite and energy intake persist in the hours following the end of hypoxic exposure? Researchers will compare the effects of simulated high-altitude to a control normoxia (sea-level) condition to see if exposure to low oxygen levels independently affect appetite and energy intake. Participants will: * Visit the laboratory for a preliminary screening session to assess eligibility. * Undergo two randomized, single-blind, experimental sessions consisting of six hours of passive exposure to normoxia or hypoxia in a climate-controlled chamber. * Consume foods provided from a curated list, served in ad libitum quantities, after leaving the laboratory to assess post-exposure energy intake.

Investigation of the Effect of Date Consumption on Hedonic Hunger and Appetite in Adult Individuals With Type 2 Diabetes

The aim of this study was to investigate the effects of date consumption on hedonic hunger and appetite hormones in individuals diagnosed with type 2 diabetes.The main questions it aims to answer are: * Does date consumption reduce hedonic hunger in individuals with type 2 diabetes? * Does persimmon consumption change Ghrelin, GLP-1 and GIP concentrations in individuals with Type 2 diabetes? * Does persimmon consumption reduce HOMA-IR and HbA1c values in individuals with Type 2 diabetes? * Does consumption of persimmon reduce LDL cholesterol, total cholesterol and triglyceride concentrations in individuals with type 2 diabetes? To see the effects of date consumption on hedonic hunger and appetite hormones, the researchers will compare individuals with type 2 diabetes who consume 3 dates daily with individuals with type 2 diabetes who do not. Participants: * Individuals in the intervention group will consume 3 (25 g) Baghdad dates (15 g CHO) daily as part of the breakfast meal, while individuals in the control group will not consume dates. * Three interviews will be conducted with patients. * A record of blood findings and questionnaires will be kept during these interviews.

Assessment of the Effects of Acute Exposure to Cold and Heat on Appetite

Military personnel and athletes have a very high energy expenditure, which is increased during certain key periods (intense training, competition and missions). Compensating for this expenditure through adequate energy intake can be complicated by physiological ingestive limits and logistical and organizational constraints (number of meals, food availability), leading these populations to regularly find themselves in an energy deficit situation (intake below requirements). If this situation persists, it could impair physical and cognitive performance, as well as major physiological functions. Among the many constraints to which military personnel and athletes are subjected (stress, sleep deprivation, travel, etc.) that can increase the risk of energy deficiency, the impact of thermal environmental constraints is very imperfectly known. Seasonal impact and travel to countries with very different thermal environments from temperate countries can lead these populations to work in cold and hot conditions for long periods. Understanding how exposure to hot and cold alters appetite and energy intake is therefore of the high importance. Our previous "TEMPCA" study highlighted a modulation of preferences for warm or cold foods depending on the exposure environment. By being able to adapt their food intake to these preferences, subjects were able to maintain a decent energy intake. The primary objective of this study is to determine the effect of the temperature of the food served (hot or cold) on changes in food intake during acute exposure to hot and cold. We hypothesized that adapting the temperature of the food served according to the exposure environment (hot in a cold environment and cold in a hot environment) would enable adequate levels of energy intake. Secondary objectives are to determine the influence of the environment on the levels of interstitial glucose during the preprandial period and to investigate the impact of thermal exposure (modulation of core temperature) on the modulation of quantities consumed and energy produced by digestion (postprandial thermogenesis). Forty participants (between 18 and 40 yo, male or female, active, lean, and healthy) will carry out 3 experimental sessions in which only the thermal environment will differ: cold condition (15°C), neutral condition (25°C) and warm condition (35°C). They will be divided into two groups, the first of which will be offered a cold meal during the three sessions (Cold Meal - CM) and the second a warm meal during the three sessions (Warm Meal - WM). They will all wear the same outfit designed to be offer perfect thermal comfort at 25 °C. Briefly, each session will start at 8:30am after eating a standardized breakfast. Body mass and ad libitum water intake will be frequently monitored to identify possible dehydration. Thermal comfort and sensation and subjective appetite will be regularly assessed using visual analog scale. From 11:00am to 01:00pm, all participants will be isolated and all temporal cues will be removed. At 01:00pm, an ad libitum meal (warm or cold) will be served in large quantities. The dishes will be weighed before and after the meal to assess energy intake. Before and after the meal, resting metabolism will be measured during 30 min in a supine position using indirect calorimetry and food preferences for high-fat/low-fat, savory/sweet, warm/cold foods, and fluid/solid foods will be assessed using the Leeds Food Preference Questionnaire.

Exogenous Ketones and Appetite

People with obesity have different appetitive responses to stimuli compared to people without obesity. For example, people with obesity have a blunted postprandial ghrelin ('hunger' hormone) response, lower glucagon-like peptide 1 (GLP-1) and peptide-YY (PYY; associated with satiety) compared to people without obesity. Given the favorable effects of exogenous ketones on appetite previously observed in healthy adults of normal body weight, it is possible that these supplements can alter appetite hormones in a manner that may closer match that observed in people without obesity. To explore this research question, investigators will conduct a randomized single-blind cross over study to characterize appetite and dietary intake after ingestion of an exogenous ketone supplement within adults with obesity (compared a control condition without exogenous ketones) and compared to adults without obesity. The research team will also explore differences in postprandial energy expenditure and fuel utilization. Twenty-two healthy young- and middle-aged adults will be included (up to n=26 enrolled). In addition to a baseline visit to measure body composition, participants will undergo two 4.5-hour study visits, one of which will include a ketone diol supplement and one will have a placebo. Participants will be given a 1-day run-in diet prior to each study day to support energy balance. On each study day visit, participants will undergo a resting metabolic rate test (indirect calorimetry) followed by a fasting appetite rating and blood sample collection. Participants will then be provided with a standard breakfast meal (one with the ketone supplement and one with placebo). Appetite ratings and blood sample collection will be repeated 60, 120, and 180 minutes after the meal. Indirect calorimetry will be completed after the 30, 90, and 150 minute assessments. After the 180-minute timepoint, participants will be provided with a buffet-like lunch meal with instructions to eat as much or as little as they would like to determine ad libitum dietary intake at a single meal. To assess free-living ad libitum dietary intake, participants will receive 1.5 days of food boxes tailored to their preferences, with uneaten food returned at the end of the 1.5-day period. This study will be the first to assess the impact of exogenous ketones on appetite in obesity and would help inform future weight loss intervention trials.