Cocoa flavanols are plant-derived bioactives from the cacao bean and in a study published in Age, two groups of 22 young (<35 years of age) and 20 older (50-80 years of age) healthy men consumed either a flavanol-containing drink, or a flavanol-free control drink, twice a day for two weeks. The researchers then measured the effect of flavanols on hallmarks of cardiovascular aging, such as arterial stiffness (as measured by pulse wave velocity), blood pressure and flow-mediated vasodilation (the extent to which blood vessels dilate in response to nitric oxide).
They found that vasodilation was significantly improved in both age groups that consumed flavanols over the course of the study (by 33% in the younger age group and 32% in the older age group over the control intervention). In the older age group, a statistically and clinically significant decrease in systolic blood pressure of 4 mmHg over control was also seen.
Improving cardiovascular health and lowering the risk of CVD
In the second study, published in BJN, the researchers extended their investigations to a larger group (100) of healthy middle-aged men and women (35-60 years) with low risk of CVD. The participants were randomly and blindly assigned into groups that consumed either a flavanol-containing drink or a flavanol-free control drink, twice a day for four weeks. The researchers also measured cholesterol levels in the study groups, in addition to vasodilation, arterial stiffness and blood pressure. “We found that intake of flavanols significantly improves several of the hallmarks of cardiovascular health,” says Professor Kelm.
In particular, the researchers found that consuming flavanols for four weeks significantly increased flow-mediated vasodilation by 21%. Increased flow-mediated vasodilation is a sign of improved endothelial function and has been shown by some studies to be associated with decreased risk of developing CVD. In addition, taking flavanols decreased blood pressure (systolic by 4.4 mmHg, diastolic by 3.9 mmHg), and improved the blood cholesterol profile by decreasing total cholesterol (by 0.2 mmol/L), decreasing LDL cholesterol (by 0.17 mmol/L), and increasing HDL cholesterol (by 0.1 mmol/L).
The researchers also calculated the Framingham Risk Score – a widely used model to estimate the 10-year cardiovascular risk of an individual – and found that flavanol intake reduced the risk of CVD. “Our results indicate that dietary flavanol intake reduces the 10-year risk of being diagnosed with CVD by 22% and the 10-year risk of dying from coronary heart disease or CVD by 37%,” says Professor Kelm.
The combined results of these studies demonstrate that flavanols are effective at mitigating age-related changes in blood vessels, and could thereby reduce the risk of CVD in healthy individuals. The application of 10-year Framingham Risk Scores should be interpreted with caution as the duration of the BJN study was weeks not years and the number of participants was around 100, not reaching the scale of the Framingham studies.
Link:
http://link.springer.com/article/10.1007%2Fs11357-015-9794-9?source=scie...