Hot chocolate

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BIRMINGHAM, United Kingdom — A cup of hot chocolate can be a perfect accompaniment to a snowy day. Now, researchers say drinking some cocoa may also be great for relieving stress. Their study finds consuming flavanols — abundant in many fruits, vegetables, and cocoa — can protect against damage due to mental stress.

A team from the University of Birmingham adds this is especially good news for heart health. The findings reveal eating and drinking flavanol-rich foods lower the risk of mental stress-induced cardiovascular events like a stroke, heart disease, or thrombosis — blood clots in a deep vein, like in the leg.

Researchers say blood vessels functioned better while enduring mental stress when participants in their study drank flavanol-rich cocoa. Scientists explain that the endothelium provides critical help in reducing the risk of several conditions, including vascular disease, stroke, heart disease, diabetes, kidney failure, tumor growth, and thrombosis. This thin membrane lines the heart and blood vessels and needs to be in top form to do its job.

“We found that drinking flavanol-rich cocoa can be an effective dietary strategy to reduce temporary impairments in endothelial function following mental stress and also improve blood flow during stressful episodes,” says lead author Dr. Catarina Rendeiro from Birmingham’s School of Sport, Exercise and Rehabilitation Sciences in a university release.

“Flavanols are extremely common in a wide range of fruit and vegetables. By utilizing the known cardiovascular benefits of these compounds during periods of acute vascular vulnerability (such as stress) we can offer improved guidance to people about how to make the most of their dietary choices during stressful periods.”

Finding heart health in a cup of cocoa?

During the study, a group of healthy men consumed a high-flavanol cocoa drink 90 minutes before engaging in an eight-minute mental stress challenge. Researchers then measured blood flow and heart activity while the group was under stress and at rest.

The results reveal stress is less able to impair blood vessel function when participants ingest flavanols. The team also discovered that flavanols provide a boost in blood flow while someone is under stress.

Researchers note that stress runs rampant through today’s society, with links to both physical and mental health problems. Mental stress can cause an immediate rise in heart rate and blood pressure in healthy adults. Study authors add it can also temporarily impair the function of the arteries, even after the trauma has stopped.

The study finds even a single stressful incident can raise your risk for cardiovascular events. Previous reports by this study’s co-investigator, Dr. Jet Veldhuijzen van Zanten, discovered that those at risk for heart disease generally have poorer vascular responses to stress.

“Our findings are significant for everyday diet, given that the daily dosage administered could be achieved by consuming a variety of foods rich in flavanols – particularly apples, black grapes, blackberries, cherries, raspberries, pears, pulses, green tea and unprocessed cocoa. This has important implications for measures to protect the blood vessels of those individuals who are more vulnerable to the effects of mental stress,” Dr. Rendeiro concludes.

Heart disease is the number one cause of death in the world. According to the Centers for Disease Control and Prevention, one in four Americans will die from cardiovascular issues each year.

The study appears in the journal Nutrients.

About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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