Healthy Underweight, Normal Weight Adults
Conditions
Keywords
Healthy underweight, Energy metabolism, Energy intake, Food preferences, Eating behavior, High-fat feeding
Brief summary
This study evaluates eating behavior and metabolic responses following consumption of a high-fat high-energy meal in healthy underweight and normal-weight adults. The primary research question is: Do healthy underweight individuals exhibit different eating and metabolic responses compared with normal-weight adults following consumption of a high-fat high-energy meal?
Detailed description
Healthy underweight individuals have a body mass index below the normal range in the absence of a medical condition, food aversion, food insecurity, or evidence of unusually high levels of physical activity. Although the environmental factors contributing to their lower body mass index are not fully understood, these individuals may represent a phenotype resistant to the obesogenic environment. If so, the biological mechanisms underlying this resistance remain poorly understood. Such mechanisms must ultimately influence energy expenditure, energy intake, or both. This study will compare metabolic responses and eating behavior during fasting and following consumption of a high-fat, high-energy meal in healthy underweight and normal-weight adults. Eating behavior will be assessed through measures of food liking, subjective appetite perceptions, and ad libitum energy intake. Metabolic responses will include assessments of energy expenditure, substrate oxidation, and circulating metabolites and hormones. We hypothesize that healthy underweight individuals will exhibit greater postprandial satiety and lower ad libitum energy intake than normal-weight adults.
Interventions
OTHERHigh-fat high-energy meal
Following an overnight fast, participants will consume a standardized high-fat high-energy meal under controlled laboratory conditions. During the subsequent postprandial period, appetite sensations, energy expenditure, circulating biomarkers, and food intake will be assessed. Food intake will be evaluated using an ad libitum meal test consisting of two sequential phases involving foods with different sensory and nutritional characteristics.
Sponsors
Jose Galgani
Agencia Nacional de Investigación y Desarrollo
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 25 Years
Healthy volunteers
No
Inclusion criteria
* Men or women * Age 18-25 years * Stable body weight during the previous 6 months (±2 kg) * Healthy according to medical history and laboratory assessments * BMI: 15.0-\<18.5 kg/m2 or 20.0-\<25.0 kg/m2
Exclusion criteria
* Pregnancy or lactation * Athletes or individuals engaged in high levels of physical activity, including those participating in competitive sports, structured endurance training, or physically demanding occupations. * Cardiovascular, liver, kidney, thyroid, or other chronic diseases requiring medical treatment * Conditions affecting energy metabolism or eating behavior * Smoking or alcohol abuse * Phobia or vasovagal response associated with blood draws * Intolerance or allergy to peanuts, chocolate, eggs, or gluten * Irregular menstrual cycles (\>3 months without menstruation) * Current or previous diagnosis of eating disorders * Psychiatric disorders requiring antidepressant or psychotropic treatment Additional criterion for healthy underweight participants: * Absence of food insecurity * Low body weight not attributable to eating disorders or exercise-related behaviors
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Total ad-libitum energy intake | The feeding test will be conducted 6.5 hours after the high-fat, high-energy meal. | Total energy intake consumed during the ad libitum feeding test. Participants will be provided with a selection of foods and instructed to eat ad libitum until comfortably satiated. The weight of each food item will be recorded before and after consumption, and intake will be determined from the difference. Total energy intake (kcal) will be calculated from the nutrient composition of the foods consumed using standard energy conversion factors. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Food liking | Measured during the screening visit. | Food liking will be assessed in the fasted state using a computerized questionnaire comprising 67 foods commonly available in retail food stores. The food list includes a wide variety of items differing in energy density, macronutrient composition, degree of processing, and sensory characteristics, including fruits, vegetables, legumes, grains, dairy products, meats, nuts, snack foods, and desserts. Images of the foods will be presented individually on a computer screen, and participants will rate their liking of each item using a 9-point Likert scale ranging from 1 ("dislike extremely") to 9 ("like extremely"). |
| Body composition | Measured during a dedicated body composition assessment visit. | Whole-body and regional body composition assessed by dual-energy X-ray absorptiometry (DXA). |
| Subjective appetite sensations | Repeatedly measured during the metabolic test before and following consumption of the high-fat, high-energy meal. | Appetite sensations will be assessed at fasting and during the postprandial period using 100-mm visual analogue scales. Participants will rate hunger, fullness, desire to eat, and prospective food consumption. Scores will be quantified as the distance (mm) from the left anchor, with higher scores indicating greater intensity of the rated sensation. |
| Energy expenditure and fuel oxidation | Repeatedly measured during the metabolic test before and following consumption of the high-fat, high-energy meal. | Energy expenditure and fuel oxidation will be assessed in the fasted state and during the postprandial period using indirect calorimetry. Oxygen consumption and carbon dioxide production will be measured under standardized conditions using a ventilated hood system. Energy expenditure will be calculated from respiratory gas exchange data using standard equations. Rates of carbohydrate and fat oxidation will be estimated from respiratory gas exchange measurements, with adjustments for urinary nitrogen excretion using standard stoichiometric equations. |
| Circulating metabolite and hormonal concentrations | Repeatedly measured during the metabolic test before and following consumption of the high-fat, high-energy meal. | Blood samples obtained in the fasted state and throughout the postprandial period will be analyzed for concentrations of glucose, free fatty acids, β-hydroxybutyrate, triglycerides, and insulin. Concentrations will be determined using validated clinical chemistry and immunoassay methods. |
Countries
Chile
Outcome results
None listed