An observational study in Weight Gain, Overweight and Insulin Resistance, sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Completed at 1 site in United States. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2026-11-09.
Sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) · Observational
Insulin resistance and a defect in early insulin secretion are risk factors for the development of type 2 diabetes mellitus. A recent longitudinal analysis which tracked the development of diabetes demonstrated that both insulin action and early insulin secretion deteriorate as individuals progress from normal to impaired glucose tolerance and then to diabetes. These results suggest that both inherent (apparent in normal glucose tolerant subjects who progress to diabetes and likely to have a genetic basis) and acquired (evident as individuals progress from NGT to IGT to diabetes and possibly environmental in origin) defects in insulin action and secretion contribute to the pathogenesis of type 2 diabetes. To identify the genetic and environmental determinants of diabetes we are continuing to determine: (1) if there are genes that segregate with metabolic risk factors for diabetes which might therefore be genetic markers for type 2 diabetes and (2) the mechanisms mediating genetic and environmental determinants of insulin resistance and impaired insulin secretion.
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Volunteers for this study will be admitted to the clinical research ward where they will undergo several tests to determine body composition, oral and intravenous glucose tolerance and in vivo insulin action. In addition, in selected subjects, adipose and/or skeletal muscle tissue will be obtained by percutaneous biopsy for in vitro studies of gene expression and insulin action in these tissues. A transformed lymphocyte cell line will be established for each subject as a permanent source of DNA for genetic studies. Genetic markers for type 2 diabetes and insulin resistance will be sought by typing each individual at positional and functional candidate loci in the hopes of finding an association between these loci and obesity, insulin secretion, insulin resistance and/or type 2 diabetes.
Insulin resistance and a defect in early insulin secretion are risk factors for the development of type 2 diabetes mellitus. A recent longitudinal analysis which tracked the development of diabetes demonstrated that both insulin action and early insulin secretion deteriorate as individuals progress from normal to impaired glucose tolerance and then to diabetes. These results suggest that both inherent (apparent in normal glucose tolerant subjects who progress to diabetes and likely to have a genetic basis) and acquired (evident as individuals progress from NGT to IGT to diabetes and possibly environmental in origin) defects in insulin action and secretion contribute to the pathogenesis of type 2 diabetes. To identify the genetic and environmental determinants of diabetes we are continuing to determine: (1) if there are genes that segregate with metabolic risk factors for diabetes which might therefore be genetic markers for type 2 diabetes and (2) the mechanisms mediating genetic and environmental determinants of insulin resistance and impaired insulin secretion.
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Volunteers for this study will be admitted to the clinical research ward where they will undergo several tests to determine body composition, oral and intravenous glucose tolerance and in vivo insulin action. In addition, in selected subjects, adipose and/or skeletal muscle tissue will be obtained by percutaneous biopsy for in vitro studies of gene expression and insulin action in these tissues. A transformed lymphocyte cell line will be established for each subject as a permanent source of DNA for genetic studies. Genetic markers for type 2 diabetes and insulin resistance will be sought by typing each individual at positional and functional candidate loci in the hopes of finding an association between these loci and obesity, insulin secretion, insulin resistance and/or type 2 diabetes.
317 studies on the registry are indexed under Weight Gain; 48 are open to participants now.
This study's enrollment of 1,759 is above the median of 110 across 53 observational studies indexed under Weight Gain.
Browse Weight Gain studies →National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) is the lead sponsor of 538 studies on the registry; 55 are open to participants now.
Of its 80 completed or terminated interventional studies of FDA-regulated products, 51 (64%) have results posted.
Counted across the registry records on this site, refreshed daily.
Community sample from eligible participants from greater Phoenix metropolitan area@@@@@@
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Subjects from all racial and ethnic backgrounds will be invited to participate if they are:
EXCLUSION CRITERIA:
Subjects will be excluded who are:
All medications and alcohol consumption are to be stopped for two weeks prior to admission. A urine drug-screening test for drugs such as narcotics, marijuana, and barbiturates will be performed on everyone to exclude from the study people whose urine show active or recent drug use. A positive drug test could confound the results of the study in an unpredictable manner. The results of this test will become a part of the patient s medical records and may be released if requested (please see page 6 of the consent for details regarding medical records release).
Volunteers aged 18-55 who are healthy as determined by medical history, physical examination, and laboratory tests
Glucose tolerance via oral glucose tolerance test (OGTT)
Measured via OGTT after ingestion of 75 grams of glucose over 2 minutes
Time frame: Baseline, and after 180 minutes on day 4
Glucose tolerance via intravenous glucose tolerance test (IVGTT)
Measured via IVGTT after administration of a glucose bolus (25 g as a 50% solution injected over 3 minutes)
Time frame: Baseline and after 10 minutes on day 5
Basal endogenous glucose production
Assessed using deuterium (D-6,6 2H) glucose as a tracer, infused as a 10 mL bolus followed by 0.150 mL/min for a total of 350 minutes
Time frame: Baseline, and after 100 minutes on day 10
24-hour metabolic rate
Assessed from the rates of caloric expenditure and substrate utilization while in the human respiratory chamber for 24 hours
Time frame: Baseline and after 23.5 hours on day 7
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 ↗
This study is completed, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) →