Comparison of Pure Epicatechin and Cocoa on Markers of Vascular Function

Twenty male participants between the ages of 40 and 80 will visit the university on three days, separated by a 2-week washout. During each visit the participants will, in random order, be allocated to one of the three interventions:

• High flavan-3-ol chocolate (70g) plus placebo capsule;
• White chocolate (70g) plus 100mg of epicatechin in capsule form;
• White chocolate (70g) plus placebo capsule; Measurements of vascular function will be taken before, and 2 hours after consumption of the supplements. In order to determine flavonoid bioavailability, 24-hour urine samples will be collected and 7 blood samples will be taken over a period of 8 hours.

The primary study parameter is the percentage change in Flow-Mediated Dilation (FMD) as a result of a high-flavonoid cocoa or epicatechin challenge. Additional study parameters include plasma flavonoid and nitric oxide concentrations as well as pulse wave analysis parameters.

Inclusion criteria

• Age between 40 and 80 years,
• BMI between > 20 and ≤ 30
• No reported current or previous metabolic diseases,
• No history of cardiovascular diseases,
• No history of renal, liver or thyroid diseases,
• No history of gastrointestinal diseases,
• No diagnosed diabetes mellitus,
• Fasting laboratory parameters within normal range as judged by the study physician: renal function (serum creatinine, ureum), liver function (ALAT, ASAT, GGT), serum glucose and HDL, LDL and total cholesterol.

Exclusion criteria

• Body mass index >30 or ≤20 kg/m2
• Usage of CVD medication (e.g. anti-hypertensive and/or lipid-modifying medication, non-steroidal anti-inflammatory drugs, acetylsalicylic acid), antibiotics, corticosteroids or opioids and not able or willing to stop taking them from at least 4 weeks prior to the study
• Taking nutritional supplements and unwilling to discontinue
• Reported dietary habits: medically prescribed diet, slimming diet
• Reported average alcohol consumption greater than or equal to 3 glasses/d
• Reported intense sporting activities > 10 h/w
• Weight loss or weight gain of 5 kg or more during the last 2 months
• Smokers
• Vegetarians
• Problems with consuming the supplements or following the study guidelines
• Recent blood donation (i.e. 1 month) prior to the study and/or planned donation during and shortly after the study period
• Not agreeing to be informed about unexpected and medically relevant personal test-results, or not agreeing that their general practitioner will be informed about these results
• Participation in another biomedical trial less than 2 months before the start of the study or at the same time
• No signed informed consent form
• Unable to comply with the study procedure (e.g. holidays, urine collection, blood sampling)