Does the Bioactive Substance in Coffee, Cafestol, Have Preventive Properties on Type-2-diabetes? (Acute Substudy)

Study Overview
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Brief Summary
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Acute, double-blinded, randomized, cross-over cafestol intervention study with fifteen participants with a large waist circumference participating in three OGTTs.

Detailed Description
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The study is a acute, double-blinded, randomized, controlled intervention in 15 subjects with abdominal obesity at high risk of developing T2D. Initially, a blood sample is obtained (t=-15 min) and at time point 0, the participants will ingest a capsule containing either 6 or 12mg cafestol or placebo. Immediately hereafter an OGTT commences with ingestion of a 75 g glucose solution. In the following 2 hours blood samples are collected at time points 15, 30, 60, 90, 120 and 180 min. The samples will be used for determination of plasma glucose, insulin and cafestol, as well as GLP-1 and GIP. After a one-week washout period, the subject will undergo the same set-up again, however now with the different dosage of cafestol or placebo. The process is repeated for three weeks until every subject has undergone both interventions and the placebo.

Official Title
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Does the Bioactive Substance in Coffee, Cafestol, Have Preventive Properties on Type-2-diabetes? Acute and Longer-term Metabolic Effects of Cafestol. (Acute Substudy)

Conditions
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Obesity, Abdominal

Intervention / Treatment
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* Dietary Supplement: Cafestol 12 mg
* Dietary Supplement: Placebo
* Dietary Supplement: Cafestol 6 mg


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 25 < BMI < 40 kg/m2 Waist circumference > 102 cm (men) / 88 cm (women) Exclusion Criteria: Type 2 diabetes (HbA1c > 48 mmol/mol) or in treatment with antidiabetic drugs Pregnancy Planned pregnancy Breastfeeding Significant comorbidity expected to unable the subject from completing visits

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cafestol 6 mg<br>6 mg cafestol | Dietary Supplement: Cafestol 6 mg<br>* Capsule with 6 mg cafestol<br>|
| Active Comparator: Cafestol 12 mg<br>12 mg cafestol | Dietary Supplement: Cafestol 12 mg<br>* Capsule with 12 mg cafestol<br>|
| Placebo Comparator: Placebo<br>Placebo | Dietary Supplement: Placebo<br>* Placebo capsule without cafestol<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the curve for glucose | Area under the curve for glucose during OGTT after ingestion of cafestol or placebo capsule (mmol/L) | -15 to 180 minutes from ingestion of intervention/placebo capsule and 75 g. glucose solution | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under the curve for insulin-response | Area under the curve for insulin response during OGTT after ingestion of cafestol or placebo capsule (pmol/L) | -15 to 180 minutes from ingestion of intervention/placebo capsule and 75 g. glucose solution | 
| Area under the curve for cafestol | Area under the curve for cafestol during OGTT after ingestion of cafestol or placebo capsule | -15 to 180 minutes from ingestion of intervention/placebo capsule and 75 g. glucose solution | 
| Area under the curve for GLP-1 (glucagon-like peptide-1) | Area under the curve for GLP-1 (glucagon-like peptide-1) during OGTT after ingestion of cafestol or placebo capsule (pmol/L) | -15 to 180 minutes from ingestion of intervention/placebo capsule and 75 g. glucose solution | 
| Area under the curve for GIP (Glucose-dependent insulinotropic polypeptide) | Area under the curve for GIP (Glucose-dependent insulinotropic polypeptide) during OGTT after ingestion of cafestol or placebo capsule (pmol/L) | -15 to 180 minutes from ingestion of intervention/placebo capsule and 75 g. glucose solution |