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Experimental Studies of the Effects of Caffeine on Glucose Regulation

This study has been completed.
Information provided by:
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Identifier:
First received: February 5, 2007
Last updated: March 1, 2010
Last verified: March 2010

February 5, 2007
March 1, 2010
July 2004
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  • postprandial glucose and insulin
  • fasting glucose and insulin
  • insulin resistance
  • glucose tolerance
Same as current
Complete list of historical versions of study NCT00432887 on Archive Site
  • epinephrine
  • norepinephrine
  • cortisol
  • blood pressure
  • plasma caffeine concentration
Same as current
Not Provided
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Experimental Studies of the Effects of Caffeine on Glucose Regulation
Caffeine and Glucose Regulation

This project contains experimental studies of the effects of the drug caffeine on glucose regulation in adults who have Type 2 diabetes. In our experiments, we are testing the hypothesis that moderate amounts of caffeine exaggerate the abnormal increases in glucose and insulin observed after meals in patients with type 2 diabetes. On separate study days subjects receive standard meals after taking capsules containing either caffeine or an inactive placebo. We measure levels of glucose, insulin, and other chemicals in blood samples drawn over the next 3 hours. In a separate study, we use continuous glucose monitoring to measure glucose levels during everyday activities on days when subjects receive caffeine or placebo.

These studies do not involve clinical treatment or disease management. However, we hope to learn whether a very popular drug impairs the clinical management of a common disease.

Pilot results suggest that caffeine, the most commonly used drug in the world, may interfere with postprandial glucose metabolism by increasing insulin resistance and/or by stimulating hepatic glucose production. This effect could have serious clinical implications for coffee drinkers who have type 2 diabetes. Early results suggest caffeine exaggerates the postprandial hyperglycemia and hyperinsulinemia present in these patients.

The experimental (non-treatment) studies in this project include double-blind placebo-controlled cross-over laboratory tests of glucose tolerance in groups of type 2 diabetic patients and prediabetic volunteers who are coffee drinkers.

The lab studies test the hypothesis that caffeine (vs. placebo) increases postprandial insulin responses and results in a potentiation of glucose responses in the type 2 group.

An ambulatory study examines the effects of caffeine administration on glucose levels during everyday activities in the natural environment. This study uses a double-blind placebo-controlled cross-over design. Ambulatory glucose data are collected with a MiniMed CGMS sensor and recorder worn for 72 hours. Caffeine and placebo are administered on separate days. Average glucose levels and glucose responses to meals are compared across treatment days within subjects.

Early Phase 1
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double-Blind
Primary Purpose: Treatment
Diabetes Mellitus, Type 2
Drug: caffeine administration
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*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
February 2007
Not Provided

Inclusion criteria:

  • 6 months or longer history of type 2 diabetes
  • treatment by diet, exercise, or oral medication
  • current daily consumption of 2 or more cups of coffee
  • BMI >21kg/M2 and < 45kg/M2

Exclusion criteria:

  • Required use of insulin
  • Current cigarette smoking
  • Current use of medications that impact glucose metabolism
  • Pregnancy
  • Other major medical disorders
Sexes Eligible for Study: All
18 Years and older   (Adult, Senior)
Contact information is only displayed when the study is recruiting subjects
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DK67486 (completed)
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National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Not Provided
Principal Investigator: James D. Lane, Ph.D. Duke University
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
March 2010

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP