Interindividual Variation in Response to Green Coffee

Exploratory Study of the Interindividual Variation in Response to Consumption of a Polyphenol-rich Green Coffee and Factor Influencing the Response

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).

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.

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