The Bioavailability of Cocoa Flavan-3-ols and Interaction With the Methylxanthine, Theobromine: a Study With Ileostomists

There is substantial interest in the potential role of chocolate and its primary bioactive component; flavan-3-ol, (-)-epicatechin, in both the prevention and management of cardiovascular disease (CVD). Numerous observational studies have found the association between high cocoa intake and a reduced CVD risk and mortality, yet the impact of these mechanisms in vivo is unclear. In order to have a beneficial effect, these cocoa flavan-3-ols must be absorbed in the body in a forms, while still maintaining its advantageous characteristics. Consumption studies with ileostomists who have had their colon removed,provide information regarding the bioavailability and bioactivity of (-)-epicatechin and flavan-3-ols from cocoa, therefore the aim of this study is to determine the impact of methylaxanthines (including theobromine) on bioavailability of cocoa flavan-3-ols prior to entering the colon.

This study has a randomised double blinded crossover control design, being applied to ileostomy patients who are aged 18-65 years, N=10, 5 per group. The study is divided into two phases. During the first phase, subjects will partake in a 2-day restriction diet (No phenolic foods) and an overnight fast prior to sampling. Ileal fluid (0hr) is obtained from participants. They will then be asked to consume the cocoa flavanol beverage dissolved in 310g 1% milk. After this urine and ieal fluid is collected every 4 hours at 3 more time points and blood every hour at 8 time points. A 24 hr urine and ieal fluid sample is collected the following day. There will be a 1-week wash out period between each phase. Procedure is repeated again for phase 2.