The clinical and cardiovascular benefits of chocolate is mounting as outlined in a recent meta-analysis by Hooper et al (2008). The polyphenol-rich food has been known for centuries to heal ailments, secure beautiful skin and provide stress relief to generations of people. In a small new study it was found that individuals who ate 75g of dark chocolate with 72% cocoa mass for two weeks experienced a reduction in blood pressure.
The cardiovascular benefits of cocoa can be ascribed to the rich epicatechin and procyanidin content. Dietary intake of cocoa or chocolate has resulted in a drop in diastolic and systolic blood pressure and reduced platelet aggregation. From a Nutrigenomics perspective, Angiotensin-converting enzyme or ACE plays a role in converting Angiotensin I to Angiotensin II which is a potent vasoconstrictor. Blood pressure (reduction) medication works by inhibiting activity of this enzyme and Cocoa works in a similar way resulting in a overall drop in Blood pressure. It was observed that this effect varies according to ACE genotype. In this new study, ACE activity was reduced by 18%Screening for ACE and AGT is already offered as part of a salt sensitivity panel as per my previous blog, and eventhough in this new study the study group is small, it may only be time before we prescribe dark chocolate before beta-blockers for specific genotypes. It is important to note that the bioavailablility of cocoa polyphenols is enhanced by the presence of fat. Therefore before we jump to encourage the intake of dark chocolate, an individualised approach should be taken to ensure that total fat intake per day is not exceeded.
As we await bigger trials, in the mean time, I will continue enjoying my hot dark chocolate and chilli drink before bed time and relax…..
To read the full study see details below
I.A.-L Persson, K. Persson, S. Hagg, R.G.G Andersson.Effects of Cocoa Extract and Dark Chocolate on Angiotensin-converting Enzyme and Nitric Oxide in Human Endothelial Cells and Healthy Volunteers–A Nutrigenomics Perspective”.Journal of Cardiovascular Pharmacology.January 2011, Volume 57, Issue 1, Pages 44-50, doi: 10.1097/FJC.0b013e3181fe62e3
Lee Hooper, Paul A Kroon, Eric B Rimm, Jeffrey S Cohn, Ian Harvey, Kathryn A Le Cornu, Jonathan J Ryder,Wendy L Hall, and Aedín Cassidy.Flavonoids, flavonoid-rich foods, and cardiovascular risk:a meta-analysis of randomized controlled trials.American journal of clinical nutrition 2008;88:38-50