Overweight and Obesity
Conditions
Keywords
Inter-individual variability, (Poly)phenols, Green coffee, Obesity, Genotype, Microbiota, Bioavailability and metabolism, Lifestyle, Cardiometabolic and inflammatory biomarkers
Brief summary
The study is a multifaceted approach to investigate the effects of regular consumption of green coffee rich in polyphenols (hydroxycinnamic acids) on weight, body composition, cardiometabolic and inflammatory biomarkers in a sample population of overweight and obese people aimed at identifying a population of responders to green coffee experimenting the highest benefit from this product, and to contribute to the understanding of the influence of some of the main factors on the response to green coffee and their association with the differences between individuals (high-responders vs. low-responders).
Detailed description
A randomized, cross-over, blind clinical trial will be carried out to evaluate the health effects of a polyphenol-rich green (slightly roasted) coffee in comparison with traditional roasted coffee to identify high- and low-responders. Participants will consume the green and roasted coffee in a randomized order during 12 weeks, separated by a 4-week wash-out (and a previous 2-week run-in). Fasting blood samples will be collected in each of the 6 visits to the research centre. Blood pressure and body composition and anthropometric variables will be measured. In addition, urine and fecal samples will be obtained at the beginning and end of each intervention stage to analyze the bioavailability and metabolism of phenolic compounds, and the intestinal microbiota, respectively. Physical activity and energy expenditure will be measured in each of the interventions. Besides a thorough cardiometabolic and inflammatory characterization of the volunteers, the frequency of specific genotypes (related with obesity, energy metabolism, inflammation and coffee intake) will be analyzed, as well as lifestyle and dietary habits of the participants, including aspects such as chrono-nutrition, sleep quality and wellbeing perception with the aim to contribute to clarify the determinants of inter-individual variability in the health effects of coffee bioactive phenolic compounds.
Interventions
DIETARY_SUPPLEMENTGreen coffee
Each cup of coffee provides approximately 400 mg of hydroxycinnamic acids.
DIETARY_SUPPLEMENTRoasted coffee
Each cup of coffee provides approximately 150 mg of hydroxycinnamic acids.
Sponsors
Ministry of Science and Innovation, Spain
Instituto de Ciencia y Tecnología de Alimentos y Nutrición
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Coffee is provided as ground coffee in unmarked 1 kg packets labeled A or B for blinding, with instructions on how to prepare the coffee brew. The polyphenol-rich coffee is slightly roasted to emulate flavor, color and aroma for blinding. Assessor will only be presented results marked as intervention A and B. Only the PIs will know the order in which both coffees were consumed by volunteers
Intervention model description
After a run-in period, participants are randomly allocated to one of each arm. Each intervention last 12 weeks, separated by a 4-week wash-out.
Eligibility
Sex/Gender
ALL
Age
20 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Body mass index 25-35 kg/m2
Exclusion criteria
* Smoking * Vegetarian/Vegan * Pregnant/lactating women * On prescription drugs other than for thyroid/hypertension/dyslipemia, or changes in dosage in the last 3 months. * Consumption of vitamins or dietary supplements * On weight-reduction dietary regime or physical training to reduce body weight * Having taken antibiotics 3 months before starting the intervention * Intestinal, hepatic or renal diseases, coffee intolerance
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Body weight | 12-week | Change in body weight (estimated 2.5 kg) at the end of the intervention |
| Body fat percentage | 12 weeks | Change in body fat percentage (total and visceral) at the end of the intervention |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Insulin levels | 12 weeks | Change in fasting blood insulin levels at the end of the intervention |
| Insulin resistance | 12 weeks | Change in homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR) index at the end of the intervention |
| Blood lipids | 12 weeks | Change in serum levels of total cholesterol or LDL-cholesterol, HDL-cholesterol or triglycerides at the end of the intervention |
| Glycated hemoglobin | 12 weeks | Change in blood levels of glycated hemoglobin (HbA1c) at the end of the intervention |
| Inflammatory cytokines | 12 weeks | Change in the levels of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNFa), interleukin (IL)-1beta, IL-2, IL-6, or anti-inflammatory IL-10 at the end of the intervention |
| Insulin sensitivity | 12 weeks | Change in quantitative insulin sensitivity check index (QUICKI) at the end of the intervention. |
| Blood glucose | 12 weeks | Change in fasting blood glucose levels at the end of the intervention |
Countries
Spain
Outcome results
None listed