Experimental Approach to Test Predictions of Body Weight Regulation Models

NCT06309576 | Recruiting

• 1 other identifier: PBRC 2023-069
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

The regulation of human body weight and fatness is not fully understood. Although some models of regulation have been proposed (set point, dual-intervention point, others), no studies have been designed to test their predictions. In this pilot and feasibility study, the investigators will implement an experimental approach to test the predictions of models of body weight regulation in humans. Men and women with either low body weight or obesity will be exposed to a 2-day fasting followed by a 2-day ad-libitum refeeding. During the entire fasting-refeeding period, energy intake and expenditure will be accurately measured within metabolic chambers. The investigators will therefore determine the compensatory responses to fasting elicited to prevent weight loss. The results will serve to design and power future studies to better understand body weight regulation.

Conditions

Obesity; Underweight

Keywords

Energy expenditure; Energy intake; Energy balance; Set point model; Dual-intervention point model

Outcome Measures

Primary Outcomes (1)

• Compensatory response

  Cumulative energy balance during the fasting-refeeding cycle

  The cumulative energy balance is calculated one time using the data of 5 inpatient days

Secondary Outcomes (12)

• Timing of the compensatory response

  The cumulative energy balance calculated for the following time periods along the 5-day fasting-refeeding cycle: day 1 to 2, day 1 to 3, day 1 to 4, during fasting (day 2 to 3), and during refeeding (day 4 to 5)

• Protein balance

  Protein balance is calculated one time using the data of 5 inpatient days

• Carbohydrate balance

  Carbohydrate balance is calculated one time using the data of 5 inpatient days

• Lipid balance

  Lipid balance is calculated one time using the data of 5 inpatient days

• Overall appetite

  Overall appetite is measured 8 times per day (every 2 hours from approximately 8:00 AM) during the 5 inpatient days

Study Arms (1)

Fasting-refeeding cycle

EXPERIMENTAL

Participants will be maintained in metabolic chambers and exposed to 1 day of energy balance, 2 days of fasting, and 2 days of ad-libitum refeeding.

Behavioral: Fasting-refeeding cycle

Interventions

Fasting-refeeding cycle BEHAVIORAL

Participants will be maintained in metabolic chambers and exposed to 1 day of energy balance with a standard diet, 2 days of fasting (only water), and 2 days of ad-libitum refeeding using a liquid diet provided in hydration bladders to avoid portion control.

Fasting-refeeding cycle

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Body mass index lower than 20 kg/m2 for the low body weight group, or 30 kg/m2 or greater for the obesity group
• years old
• Nulliparous and regular menstrual cycle (25-35 days) during the last six months (in women)
• Normal thyroid function, blood count, and chemistry 15 panel (normal plasma glucose will be considered at \<100 mg/dL; normal serum HDL cholesterol at \>=50 mg/dL for women and \>=40 mg/dL for men; and normal serum triglycerides at \<150 mg/dL).
• Self-reported weight stability during the last six months (±3 kg)
• Rate the liking of at least one of the flavored liquid meals (Ensure Plus, Abbot Nutrition) between 5 and 8 on a 9-point Likert scale
• Willing to only drink up to two assigned flavors of Ensure Plus for two consecutive days

You may not qualify if:

• Eating disorders as indicated by a global score ≥2.80 in the Eating Disorder Examination Questionnaire, or a previous diagnosis of an eating disorder
• For the low body weight group, having food insecurity (with or without hunger) as assessed by the USDA
• Recreational moderate-intensity physical activity ≥150 min/week, recreational vigorous-intensity physical activity ≥75 min/week, or a combination of recreational moderate-intensity and vigorous-intensity physical activity (moderate time + \[2 × vigorous time\]) ≥150 min/week as assessed by the Global Physical Activity Questionnaire, or being a professional athlete
• Cigarette or vape smoking
• Intake of more than 14 alcoholic drinks per week
• Use of medications that may affect energy intake and/or expenditure, for example, semaglutide, liraglutide, exenatide, other GLP-1 receptor agonists, phentermine-topiramate, naltrexone-bupropion, orlistat, metformin, SGLT2 inhibitors, pramlintide, levocarnitine, amphetamines, and amphetamine-like drugs
• Human immunodeficiency virus, galactosemia, and lactose intolerance
• Diseases that affect energy homeostasis including endocrine such as hypo/hyperthyroidism, or type 1 or 2 diabetes; cancer; chronic pulmonary diseases; cardiovascular disease; and renal disease
• History of inflammatory bowel disease (ulcerative colitis, Crohn's), malabsorption syndromes (intestinal, pancreatic), and sprue or gluten intolerance
• Having moderate to severe sleep apnea defined as an oxygen desaturation index \&gt;10 times/hour assessed by overnight oximetry to be conducted on the night following the screening visit
• Use of oral hormonal contraceptives or less than 6 months using a hormonal intrauterine device (in women)
• Adults who are unable to consent
• Prisoners
• Currently pregnant or breastfeeding (in women)

Sponsors & Collaborators

• Pennington Biomedical Research Center: lead
• Tulane University: collaborator

Study Sites (1)

Pennington Biomedical Research Center

Baton Rouge, Louisiana, 70808, United States

RECRUITING

MeSH Terms

Conditions

Obesity; Thinness

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Rodrigo Fernandez-Verdejo, PhD

  Pennington Biomedical Research Center

  PRINCIPAL INVESTIGATOR

• Eric Ravussin, PhD

  Pennington Biomedical Research Center

  PRINCIPAL INVESTIGATOR

• Dragana Lovre, MD

  Tulane University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Rodrigo Fernandez-Verdejo, PhD

CONTACT

2257632594; Rodrigo.Fernandez@pbrc.edu

Eric Ravussin, PhD

CONTACT

2257633186; Eric.Ravussin@pbrc.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Visiting Assistant Professor

Study Record Dates

• First Submitted: March 1, 2024
• First Posted: March 13, 2024
• Study Start: January 17, 2025
• Primary Completion (Estimated): May 30, 2026
• Study Completion (Estimated): June 30, 2026
• Last Updated: December 4, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF
• Time Frame: After publication of the results for the main outcome
• Access Criteria: Upon appropriate request

Locations

US (1)