NCT05545306Recruiting

The Effects of Increasing Caloric Intake on Diet-Induced Thermogenesis and 24h Energy Expenditure

Source: ClinicalTrials.gov · Last updated 28 Aug 2026

Brief summary (registry, in English)

Background: Diet-induced thermogenesis (DIT) is the amount of energy one's body uses to eat food, absorb the nutrients from the food, and process those nutrients. Researchers would like to understand more about how changing the balances of protein, fat, carbohydrates, and total calories in the diet can affect DIT. Objective: To learn how different diets can change a person's DIT. Eligibility: Healthy people aged 18 to 60 years who have not intentionally lost weight in the past 6 months. Design: Participants will stay in a clinic for about 35 days. They will eat only the food provided. They will receive 8 different diets during the study, including 7 test diets. Participants will undergo multiple tests. They will be screened with blood and urine tests and a test of their heart function. During the first few days: Their waist, thigh, and neck circumference will be measured. They will have a DXA scan: They will lie on a padded table for about 20 minutes while an instrument measures the amount of fat in their body. They will be tested for diabetes. They will answer questionnaires about topics including eating behavior, hunger, and stress. Throughout the study: Their weight will be measured daily. Blood tests will be repeated. They will stay in a metabolic chamber a total of 9 times. They will remain in a closed room for 24 hours while researchers monitor the room temperature and levels of oxygen and carbon dioxide. Participants will collect all their urine for each 24-hour period. ...

Status (registry): Recruiting
Study type: Interventional
Enrollment: 120 (estimated)
First submitted: 16 Sept 2022
Start date: 6 Jun 2023
Primary completion date: 2 Feb 2027
Lead sponsor: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Diseases: Obesity
NCT number: NCT05545306

What you commit to

Study type: Interventional
Planned participants: 120
From 6 Jun 2023 to the primary completion date, 2 Feb 2027
1 site in 1 country
Visits and tests: ask the trial team, the registry does not list them

Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.

Who cannot take part

Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.

Prior treatment

Central nervous system disease:
- including history of previous history of cerebrovascular accidents, dementia, and neurodegenerative disorders
Current use of illegal drugs such as amphetamines, cocaine, opiates, or heroin; use of marijuana is permitted.
Current use of medications/dietary supplements/alternative therapies known to alter energy metabolism

Other illness

history of type 1 or type 2 diabetes
- -Endocrine disorders, such as
History of Cushing s disease, pituitary disorders, or hypo- and hyperthyroidism
Pulmonary disorders
- History of chronic obstructive pulmonary disease or other lung disease that which would limit ability to follow the protocol (investigator judgment)
Cardiovascular diseases,
- Including history of coronary heart disease, heart failure, arrhythmias, and peripheral artery disease
Hypertension,
- History of diagnosis and current treatment by an outside clinician
or sitting blood pressure measurement, using an appropriate cuff, higher than
- 140/90 mmHg
- -Liver disease,
including history of cirrhosis, active hepatitis B or C
Cancer:
- History requiring treatment in the past five years, except for non-melanoma skin cancers or cancers that have clearly been cured or in the opinion of the investigator carry an excellent prognosis (e.g., Stage 1 cervical cancer).
Infectious disease:
- History of active tuberculosis, HIV chronic coccidiomycosis or other chronic infections
Conditions not specifically mentioned above may serve as criteria for exclusion at the discretion of the investigators
History of psychological conditions including (but not limited to) claustrophobia, clinical depression, bipolar disorders, or forms of mental incapacity that would be incompatible with safe and successful participation in this study

Lab values

Diabetes
- Fasting glucose \>= 126 mg/dl or hba1c \>= 6.5% or
AST or ALT \>=3 times upper limit of normal on screening labs
Renal disease
- Serum creatinine \>= 1.5 mg/dls
Abnormal kidney function (eGFR \<60 mL/min/1.73m\^2)

Other

An individual who meets any of the following criteria will be excluded from participation in this study:
Current use of tobacco products that exceed "Very Low Dependence" on the Fagerstrom Test for Nicotine Dependence Tool (score greater than 2)
TSH \<0.1 or \>= 10 uIU/mL
Evidence of alcohol abuse as defined by \> =8-point score on the Alcohol consumption screening AUDIT questionnaire in adults
For Females:
- i. Pregnancy or lactation by history and urine pregnancy test
- ii. Peri- or post-menopause by self-report or irregular menstrual cycle.
Measured weight: greater than or equal to 450 lb. (maximum weight allowed on the DXA scanning tables by the manufacturer).
Inability to speak or read English by self-report.
Inability to provide informed consent
Inability to consume provided diets due to dietary concerns that will not allow them to consume \>=95% of provided calories.

Criteria the registry did not label

INCLUSION CRITERIA:
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
Male or female, aged 18-60 years old
No episodes of intentional weight loss over previous 6 months

Age in the registry: 18 years to 60 years · Sex: All · Accepts healthy volunteers

Full criteria on ClinicalTrials.gov

Sites (1)

Sites in registry order. Pick your city on the disease page to sort them by distance.

Site	City	Country	Site status
NIDDK, Phoenix Coordinator of this site? Confirm its status	Phoenix	United States	Recruiting

This page is information, not medical advice. Discuss any trial with your doctor.