N/A
N=54
Food Intake Response to Short-Term Modifications of Metabolism in Humans
Healthy Volunteers
Bottom Line
View on ClinicalTrials.gov: NCT02939404 ↗Enrolled (actual)
54
Serious AEs
0.0%
Results posted
Jul 2025
Primary outcome: Primary: 24-hour Energy Expenditure (kcal) — 2256; 2166; 2563; 2487 kcal
Study Design & Population
- Study type
- Interventional
- Phase
- N/A
- Interventions
- Cold exposure (Other); Normal temperature (Other); Fixed diet (Other); Ad libitum diet (Other); Fasting (Other)
- Age
- Adult · 18+ yrs
- Sex
- All
- Sponsor
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
- Primary completion
- Jun 2024
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY 24-hour Energy Expenditure (kcal) |
2256; 2166; 2563; 2487; 2271; 2153 | — |
| PRIMARY 24-hour Energy Intake (kcal) |
3811; 3694; 4091; 4359; 4014; 4075 | — |
| SECONDARY 24- Hour Respiratory Quotient (RQ) |
0.868; 0.868; 0.925; 0.935; 0.872; 0.867 | — |
| SECONDARY Leptin |
26.1; 26.5; 29.5; 27.8; 18.3; 16.6 | — |
| SECONDARY Secretin |
0.91; 0.91; 1.03; 1.00; 0.99; 1.01 | — |
| SECONDARY Ghrelin |
502; 644; 544; 605; 575; 581 | — |
| SECONDARY FGF-21 |
94; 98; 98; 113; 106; 108 | — |
| SECONDARY Core Body Temperature (C) |
36.98; 37.02; 36.97; 36.95; 36.98; 36.98 | — |
| SECONDARY Weight Change at 6 Months |
0.3; -0.5 | — |
| SECONDARY Weight Change at 12 Months |
1.0; -0.6 | — |
Summary
One reason people gain weight is eating more calories from food than what they need for energy over 24 hours. Metabolism is the amount of energy a person uses over 24 hours. Researchers want to study the relationship between changes in metabolism and how much a person eats.
Objectives:
To see how much food a person eats when the body's temperature is cooled. To study how changes in metabolism may alter the amount of food a person eats.
Eligibility:
Healthy people ages 18-55.
Design:
Participants will stay at NIH for 20 days.
During the first 4 days, participants will have:
* Medical exam
* Electrocardiogram
* Blood and urine tests. One blood test includes drinking a sugar solution.
* DXA body composition scan
* Questions about foods they like, physical activity, and personal behavior
* Exercise test on a stationary bicycle
Participants will spend 24-hour periods in a metabolic chamber. The chamber will be at normal room temperature or cooler.
Some times, participants will eat a diet that matches their daily needs (fixed or eucaloric). Other times, they can eat as much as they wish from a vending machine (ad libitum).
Participants will have blood and urine collected.
Participants will swallow an ingestible wireless sensor and wear a small data recorder device.
On the second to last day, participants will stay in the metabolic chamber but only consume water and non-caffeinated sugar-free beverages.
Participants will come back for 1-day visits at six months and one year from the first admission. They will have blood and urine tests, and a DXA scan. They will answer questions on physical activity and food habits.
Eligibility Criteria
- INCLUSION CRITERIA:
- Premenopausal women and men = 36 kg (>= 80 pounds)
- Stable weight (+/-5% within past 6 months) as determined by volunteer report
- Healthy, as determined by medical history, physical examination, and laboratory tests
EXCLUSION CRITERIA
- Age <18 years
- Weight greater than or equal to 204 kg (greater than or equal to 450 pounds, maximum weight of the iDXA machine as per manufacturer s manual), or weight <36 kg (<80 pounds, minimum weight allowed based on the NIH guidelines of blood drawing for research purposes)
- Use of medications affecting metabolism and appetite in the last three months
- Expresses unwillingness to consume all food given during the weight maintaining diet portions of the study (e.g., due to strict dietary restrictions including allergies or vegetarian or kosher diet)
- Current use of tobacco products, marijuana, amphetamines, cocaine, or intravenous drug use
- Current pregnancy, pregnancy within the past 6 months or lactation
- History or clinical manifestation of:
- Type 1 and Type 2 diabetes mellitus
- History of surgery for the treatment of obesity
- Endocrine disorders, such as Cushing s disease, pituitary disorders, and hypo and hyperthyroidism
- Pulmonary disorders, including chronic obstructive pulmonary disease
- Cardiovascular diseases, including coronary heart disease, heart failure, arrhythmias, and peripheral artery disease
- High blood pressure by sitting blood pressure measurement using an appropriate cuff higher than 140/90 mmHg on two or more occasions, or current antihypertensive therapy
- Liver disease, including cirrhosis, active hepatitis B or C, and AST or ALT greater than or equal to 2x normal
- Gastrointestinal disease including Crohn s disease, ulcerative colitis, celiac disease or other malabsorptive disorders
- Abnormal kidney function (eGFR <60 mL/min/1.73m(2))
- Central nervous system disease, including previous history of cerebrovascular accidents, dementia, neurodegenerative disorders or history of severe head trauma
- Cancer requiring treatment in the past five years, except for nonmelanoma skin cancers or cancers that have clearly been cured
- Infectious disease such as active tuberculosis, HIV (by self report), chronic coccidiomycoses or other chronic infections that might influence EE and weight
- Diagnosis of binge eating disorder, anorexia and major psychiatric disorders based upon the DSM-IV including depression, schizophrenia and psychosis, which may impact the ability of the participant to be in the respiratory chamber for 24 hour time periods
- Chronic ethanol use (more than 3 drinks/day)
Data sourced from ClinicalTrials.gov (NCT02939404). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.