Dark chocolates perk up blood vessel function: Study

Flavanol - phytochemicals found in chocolates, fruits and vegetables, boost the function of vital endothelial cells that line up inside the blood vessels, thus decreasing the risk of cardiovascular disease, researchers at the Yale Prevention Research Center in Connecticut found.

The results of the study were presented at the annual American College of Cardiology scientific meeting in New Orleans on Sunday.

Extracting links, researchers found strong correlation between the consumption of foods rich in flavonoids.

While, cocoa or dark chocolate products are considered the most concentrated sources of flavonoids, it is also found in fruits, vegetables, wine and green tea.

Flavonoids is a group of antioxidant compounds that fights against cardiovascular disease.

Randomly dividing subjects into three consumption groups, the researchers examined 45 healthy adults with a body mass index (BMI) between 25 and 35 kg/m2 from Connecticut State for the study.

During the six-week trial the volunteers were given 8 ounces of cocoa without sugar, cocoa with sugar or a placebo each day.

On daily basis, the participants underwent Flow Mediated Dilation (FMD) – a test designed to record the upper arm brachial artery's ability to relax and expand in order to accommodate increased blood flow. Using high-frequency ultrasounds, the figures were measured before and after cocoa or placebo consumption daily.

On completion of trial, the FMD improved significantly for cocoa consumption groups as compared to the placebo group.

‘Cocoa without sugar’ consumption group recorded the highest 2.4 percent fall in FMD, thus recording the highest improved blood vessel functioning, while ‘cocoa with sugar’ consumption group posted a 1.5 percent drop.

Meanwhile, there was a 0.8 percent decrease in FMD in the group that ate the placebo.

"In this group of healthy adults with BMI between 25 and 35 kg/m2, dark chocolate ingestion over a short period of time was shown to significantly improve endothelial function, leading our team to believe that greater benefit may be seen through a long-term, randomized clinical trial," co-investigator, Dr. Valentine Yanchou Njike of Yale Prevention Research Center said.

However, cautioning against chocolate overdoing, researchers called for larger studies to generate confirmed results.

According to previous studies, flavonoid-rich foods are also known to boost the levels of nitric oxide in the blood of smokers and reverse some of their smoking-related impairment in blood vessel function.