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

Description

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. ...

Conditions

Obesity, Normal Physiology, Healthy Volunteers

Study Overview

Study Details

Study overview

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. ...

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

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

Condition
Obesity
Intervention / Treatment

-

Contacts and Locations

Phoenix

NIDDK, Phoenix, Phoenix, Arizona, United States, 85014

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

For general information about clinical research, read Learn About Studies.

Eligibility Criteria

  • * Male or female, aged 18-60 years old
  • * No episodes of intentional weight loss over previous 6 months
  • * Current use of tobacco products that exceed "Very Low Dependence" on the Fagerstrom Test for Nicotine Dependence Tool (score greater than 2)
  • * Diabetes
  • * Pulmonary disorders
  • * Cardiovascular diseases,
  • * Hypertension,
  • * Renal disease
  • * Abnormal kidney function (eGFR \<60 mL/min/1.73m\^2)
  • * Central nervous system disease:
  • * Cancer:
  • * Infectious disease:
  • * Conditions not specifically mentioned above may serve as criteria for exclusion at the discretion of the investigators
  • * Evidence of alcohol abuse as defined by \> =8-point score on the Alcohol consumption screening AUDIT questionnaire in adults
  • * Current use of illegal drugs such as amphetamines, cocaine, opiates, or heroin; use of marijuana is permitted.
  • * 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
  • * 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
  • * Current use of medications/dietary supplements/alternative therapies known to alter energy metabolism
  • * Inability to consume provided diets due to dietary concerns that will not allow them to consume \>=95% of provided calories.

Ages Eligible for Study

18 Years to 60 Years

Sexes Eligible for Study

ALL

Accepts Healthy Volunteers

Yes

Collaborators and Investigators

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK),

Tomas Cabeza De Baca, Ph.D., PRINCIPAL_INVESTIGATOR, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

Study Record Dates

2027-02-02