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Completed Not applicable Interventional Accepts healthy volunteers

Effects of Caffeinated and Decaffeinated Coffee on Body Weight and Glucose Tolerance

ClinicalTrials.gov ID: NCT00305097

Public ClinicalTrials.gov record NCT00305097. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 3, 2026, 1:32 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

Habitual consumption of coffee may have substantial beneficial effects on glucose metabolism according to recent findings of epidemiological studies in the U.S., Europe, and Japan. However, data from longer-term human intervention studies with appropriate outcome measures are lacking. We will study the effects of caffeinated and decaffeinated coffee consumption on body fatness, insulin sensitivity and glucose tolerance that may underlie the observed associations with a lower risk of type 2 diabetes in a randomized controlled trial. We hypothesize that both caffeinated and decaffeinated coffee will improve insulin sensitivity and glucose tolerance. Before starting a larger, long-term intervention study, we will conduct a pilot study to test the feasibility of such a trial. The pilot study will be an 8-week parallel trial in 45 overweight individuals, who will be randomized to drinking 5 cups per day of 1) caffeinated coffee (n=15), 2) decaffeinated coffee (n=15), or 3) water (n=15). Body fatness (weight, waist circumference, bioelectrical impedance), insulin sensitivity (HOMA model), and glucose tolerance (oral glucose tolerance test) will be the primary outcomes. We will assess the adherence of participants to their assigned treatment by measuring serum caffeine concentrations, documentation of coffee use in diaries by the participants, and counting unused coffee packets. We will also obtain feedback from participants on how to improve compliance in a future trial. If successful, this study will form the basis for a definitive trial of coffee consumption, body fatness, and glucose tolerance. Given the extensive use of coffee and the rapidly increasing health burden of type 2 diabetes, such a trial would have important public health implications.

Study identification

NCT ID
NCT00305097
Recruitment status
Completed
Study type
Interventional
Phase
Not applicable
Enrollment
45 participants

Conditions and interventions

Conditions

Interventions

Dietary Supplement

Eligibility (public fields only)

Age range
18 Years and older
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Apr 30, 2006
Primary completion
Aug 31, 2008
Completion
Aug 31, 2008
Last update posted
Mar 5, 2018

2006 – 2008

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Beth Israel Deaconess Medical Center Boston Massachusetts 02215

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT00305097, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Mar 5, 2018 · Synced Sep 3, 2026

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The complete protocol, eligibility criteria, and contact information for NCT00305097 live on ClinicalTrials.gov.

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