Effects of Coffee Roasting on Blood Sugar Levels in Healthy Humans

Not Applicable

Completed

• Conditions: Hyperglycemia
• Interventions: Dietary Supplement: Dark Roasted Coffee; Dietary Supplement: Light Roasted Coffee; Dietary Supplement: Placebo Comparator; Dietary Supplement: Medium Roasted Coffee

• Registration Number: NCT05119153
• Lead Sponsor: North Carolina State University

Brief Summary

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

Detailed Description

This is a single-blinded, randomized partial block design conducted over 6 weeks in two parts.

In part 1 (3 weeks), participants were randomly assigned to consume four beverages: a placebo containing water and caramel color, light, medium, or dark roast coffee before, during, or after consumption of a beverage containing 50 g of glucose.

In part 2 (3 weeks), participants were randomly assigned to consume four beverages: a placebo containing water and caramel color, light, medium, or dark roast coffee before, during, or after consumption of a standardized breakfast (corn flakes cereal + skim milk) containing 50 g of glucose.

In each part, fasting and postprandial glucose profiles were determined.

Study Timeline

• Study Start: 2019-11-05
• Primary Completion: 2020-12-20
• Study Completion: 2021-10-31
• Study First Submitted: 2021-10-31
• Status Verified: 2021-11
• Study First Submitted QC: 2021-11-10
• Last Update Submitted: 2021-11-10
• Study First Posted: 2021-11-12
• Last Update Posted: 2021-11-12

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 19

Inclusion Criteria

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

Exclusion Criteria

• 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

• Food allergies or intolerances to coffee/caffeine/dairy/corn-based cereals.

• Currently taking prescription medication

• Current smoker

• Consumes more than 3 alcoholic beverages per day

• Pregnant or breastfeeding

• Not willing to take their own blood samples with finger sticks

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Dark Roasted Coffee	Dark Roasted Coffee	12 oz dark roast coffee beverage prepared at 55 g ground coffee/L water
Light Roasted Coffee	Light Roasted Coffee	12 oz light roast coffee beverage prepared at 55 g ground coffee/L water
Placebo Comparator	Placebo Comparator	Placebo composed of water and caramel color.
Medium Roasted Coffee	Medium Roasted Coffee	12 oz medium roast coffee beverage prepared at 55 g ground coffee/L water

Primary Outcome Measures

Name	Time	Method
Changes in Blood Glucose	6 weeks	Each week, fasted baseline and postprandial measurements taken out to 240 minutes

Secondary Outcome Measures

Name	Time	Method
Changes in Glucose Area Under the Curve	6 weeks	Used glucose changes over 240 minutes to construct area under the curve

Trial Locations

Locations (1)

Schaub Hall, Campus Box 7624; 🇺🇸 Raleigh, North Carolina, United States