Variability In Mixed Meal Tests: Fixed Versus Adjusted to Energy Needs Caloric Dose
Eligible age
18–99 yrs
Accepts
All genders
Locations
1 state
Healthy volunteers
Yes
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About this study
Background: Researchers use mixed meal tolerance tests (MMTTs) to look at how people s bodies respond to eating a meal. However, researchers do not agree on how to decide the number of calories to give in each meal. Some use fixed meals, which are the same size for everyone, and some use adjusted meals, based on the size of the person s body. Researchers want to know which MMTT is best to use for future research. Objective: To learn how fixed vs adjusted meals affect blood glucose levels in healthy people. Eligibility: Healthy people aged 18 years or older. Design: Participants will have 3 or 4 clinic visits of up to 8 hours in 8 weeks. Participants will have baseline tests: Their height, weight, and waist size will be measured. They will have an oral glucose tolerance test: A needle attached to a tube (IV) will be inserted into a vein in the arm. They will have a sugary drink. Blood samples will be taken from the tube at intervals up to 3 hours after the drink. They will have a body scan. Participants will have 2 MMTT visits. One will include a fixed meal and one will include an adjusted meal. They will have tests at both visits: Resting metabolic rate: A clear hood will be placed over the participant s head while they rest for 20 minutes. This will measure the oxygen they breathe in and out. MMTT. Participants will have 5 minutes to drink a liquid meal. Blood samples will be taken at intervals for the next 4 hours....
Sponsor: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
You may not qualify if…
- ✕ An individual who meets any of the following criteria will be excluded from participation in this
- ✕ study:
- ✕ Current use of medications, dietary supplements, or alternative therapies known to alter energy metabolism.
- ✕ Fasting plasma glucose \>= 126 mg/dL
- ✕ Type I or Type II Diabetes Mellitus by self-report.
- ✕ Hematologic disorders including significant anemia (male hemoglobin \< 13.0 g/dL or female hemoglobin \< 11.0 g/dL)
- ✕ Current pregnancy, pregnancy within the past 6 months or currently lactating
- ✕ History or self-report of gastrointestinal disease, including inflammatory bowel diseases (e.g. Chron s disease and ulcerative colitis), malabsorption syndromes (e.g. celiac disease), gastric ulcer (active) which may alter metabolism or absorption of study food by self-report
Where it's recruiting
Phoenix
Source: ClinicalTrials.gov · NCT06223555 · last updated 2026-06-12