Effects of Coffee Roasting on Blood Sugar Levels in Healthy Humans

NCT05119153 | Completed

• 1 other identifier: 16857
• Study Type: interventional
• Target: 19
• Locations: 1 country
• Sites: 1

Brief Summary

The present study determined the effects light, medium, and dark roasted, brewed coffees on blood glucose responses in normal (n = 19) subjects.

Conditions

Hyperglycemia

Keywords

coffee; glucose challenge; blood glucose levels

Outcome Measures

Primary Outcomes (1)

• Changes in Blood Glucose

  Each week, fasted baseline and postprandial measurements taken out to 240 minutes

  6 weeks

Secondary Outcomes (1)

• Changes in Glucose Area Under the Curve

  6 weeks

Study Arms (4)

Placebo Comparator

PLACEBO COMPARATOR

Placebo composed of water and caramel color.

Dietary Supplement: Placebo Comparator

Light Roasted Coffee

EXPERIMENTAL

12 oz light roast coffee beverage prepared at 55 g ground coffee/L water

Dietary Supplement: Light Roasted Coffee

Medium Roasted Coffee

EXPERIMENTAL

12 oz medium roast coffee beverage prepared at 55 g ground coffee/L water

Dietary Supplement: Medium Roasted Coffee

Dark Roasted Coffee

EXPERIMENTAL

12 oz dark roast coffee beverage prepared at 55 g ground coffee/L water

Dietary Supplement: Dark Roasted Coffee

Interventions

Placebo Comparator DIETARY_SUPPLEMENT

Placebo designed to mimic coffee color.

Placebo Comparator

Light Roasted Coffee DIETARY_SUPPLEMENT

12 oz light roast coffee

Light Roasted Coffee

Medium Roasted Coffee DIETARY_SUPPLEMENT

12 oz medium roast coffee

Medium Roasted Coffee

Dark Roasted Coffee DIETARY_SUPPLEMENT

12 oz dark roast coffee

Dark Roasted Coffee

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-64 years old with BMI less than 29 and fasting blood glucose less than 125 mg/dl.

You may not qualify if:

• Age 18-64 years old with BMI less than 29 and fasting blood glucose less than 125 mg/dl.
• Weight less than 110 pounds (55 kg)
• Pre-existing health conditions, such as:
• High cholesterol
• Hypertension
• Cardiovascular disease
• Gastrointestinal motility disorders
• Hypo- or hyperthyroidism
• Anemia
• Renal disease
• Liver disease, including hepatitis B or C, cholestasis, cirrhotic liver disease, or non-alcoholic fatty liver disease
• Chronic or acute pancreatitis
• Diabetes type 1 or 2
• Insulin resistance
• Polycystic ovary syndrome

Sponsors & Collaborators

• North Carolina State University: lead

Study Sites (1)

Schaub Hall, Campus Box 7624

Raleigh, North Carolina, 27695, United States

Location

Related Publications (1)

• Rayo-Mendez LM, Kinzer C, McMahon J, Nguyen M, Harris GK. Coffee Roast Level, Timing, and Carbohydrate Source Affect Peak Blood Glucose and Area Under the Curve Values in a Randomized Pilot Clinical Trial. J Nutr Metab. 2025 Oct 23;2025:4174563. doi: 10.1155/jnme/4174563. eCollection 2025.

  PMID: 41179392 DERIVED

MeSH Terms

Conditions

Hyperglycemia

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Study Officials

• Gabriel K Harris, PhD

  North Carolina State University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Subjects provided placebo and coffee beverages in a color coded bottles
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor of Food Science

Model Details: Randomized, single-blinded, partial block, crossover design

Study Record Dates

• First Submitted: October 31, 2021
• First Posted: November 12, 2021
• Study Start: November 5, 2019
• Primary Completion: December 20, 2020
• Study Completion: October 31, 2021
• Last Updated: November 12, 2021

Record last verified: 2021-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)