An observational study in Metabolic Disorders, Cancer and Chronic Kidney Disease, sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Recruiting at 1 site in United States. Open to participants aged 2 Years to 99 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-06.
Sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) · Observational
Background:
Scientists have long used simple measures (such as height and weight) to estimate how much a person s body uses food (calories) as energy, as commonly called the metabolic rate. But metabolism varies among people with similar body sizes. Scientists now believe the old formulas for estimating metabolic rates may not work well for all people. Researchers want to find more accurate ways to measure a person s metabolism.
Objective:
This natural history study will examine the relationships between metabolism, body composition, and body surface area in a wide range of people.
Eligibility:
Healthy children and adults aged 2 years or older. Also, people aged 2 years or older with conditions that may alter metabolism. These may include diabetes, obesity, renal disease, or cancer.
Design:
Participants will spend 2 days and 1 night in the hospital. They will provide a medical history and answer questions about their activity levels, the foods they eat, and their lifestyle. They will also eat a special diet.
Participants will undergo many tests:
They will lie in a bed with a clear hood covering their head for 30 to 45 minutes to measure the gases in their breath.
They will lie on a padded table for about 15 minutes while their body is scanned.
They will stand on a platform while a 3D scanner measures their body.
They will have a test to measure how fast an electric signal moves through their body.
They will grip an instrument to measure the strength of their hands.
They will drink salty water and provide blood and urine samples.
Participants may be invited to return for these 2-day visits up to 8 times per year. Return visits must be at least 2 weeks apart.
Study Description:
This study will examine the relationships between comprehensively measured resting energy expenditure (REE), body composition, and body surface area (BSA) in a wide range of healthy and diseased individuals.
Objectives:
Primary Objectives:
Endpoints:
Primary Endpoints:
997 studies on the registry are indexed under Metabolic Diseases; 234 are open to participants now.
This study's planned enrollment of 2,000 is above the median of 176 across 300 observational studies indexed under Metabolic Diseases.
Browse Metabolic Diseases studies →National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) is the lead sponsor of 529 studies on the registry; 54 are open to participants now.
Of its 79 completed or terminated interventional studies of FDA-regulated products, 50 (63%) have results posted.
Counted across the registry records on this site, refreshed daily.
Local population, primary clinical, referred patients
In order to be eligible to participate in this study, an individual must meet all the following criteria for their cohort:
Cohort 1 - Healthy Volunteers
Cohort 2 - Patients
EXCLUSION CRITERIA:
An individual who meets any of the following criteria will be excluded from participation in this study:
Male and female volunteers aged 2+ years in good general health as evidenced by medical history
Male and female patients aged 2+ years diagnosed with diseases thought to alter metabolism or body composition and/or taking medication thought to alter metabolism or body composition
Increase in R^2
Increase in R2 when measured BSA is added to equations predicting REE
Time frame: Per study visit
Mean difference and limits of agreement between measured and predicted BSA
Mean difference and limits of agreement between measured BSA and predicted BSA calculated from traditional biometrics such as height and weight
Time frame: Per study visit
Plan to share: Undecided
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)