Click on image to view larger version.

Figure 1 Study Protocol

(A) Feasibility study: double-masked, randomized study design to test acute effects (red) of a single ingestion of flavanol-containing cocoa in diabetic patients, and to assess dosage regimens for long-term studies. Flow-mediated dilation (FMD) and hemodynamics were measured before and up to 6 h after consumption of a single cocoa drink available at 3 different flavanol doses (high: 963 mg of flavanols = red square; medium: 371 mg = red triangle; or control: 75 mg = red circle). Plasma flavanol metabolites were measured before and 2 h after cocoa intake. Each cocoa ingestion was separated by at least 3 days to avoid potential carry-over effects. (B) Efficacy study: double-masked, randomized, controlled, parallel-group study design to investigate the sustained effects (green) of regular daily cocoa intake on endothelial function in diabetic patients. Patients were randomized to receive cocoa containing either a cumulative dose of 963 mg of flavanols (treatment group: 3 x 321 mg daily = green squares) or 75 mg of flavanols (control group: 3 x 25 mg daily = green circles). Flow-mediated dilation, hemodynamic parameters, and plasma flavanol metabolites were measured 1 h before and 2 h after the morning cocoa drink at study entry (day 0), after 1 week (day 8), and after 1 month (day 30).