Increased consumption of flavanols – a set of molecules occurring naturally in high-flavanol cocoa, fruit and vegetables – could protect people from mental stress-induced cardiovascular events such as stroke, heart disease and thrombosis, according to new research.
Researchers have found that blood vessels could function better during mental stress when people were given high-flavanol cocoa than drinking a non-flavanol enriched beverage.
A thin membrane of cells lining the heart and blood vessels, when functioning effectively the endothelium helps to reduce the possibility of peripheral vascular disease, stroke, heart disease, diabetes, kidney failure, tumour development, thrombosis, and severe viral infectious diseases. We know that psychological stress can have a negative impact on blood vessel function.
A UK research team from the University of Birmingham analyzed the effects of high-flavanol cocoa on stress-induced affects on vascular role – publishing their findings in Nutrients.
Lead author, Dr. Catarina Rendeiro, of the University of Birmingham’s School of Sport, Exercise and Rehabilitation Sciences, explains: “We found that drinking high-flavanol 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”.
“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.”
In a randomized study, conducted by postgraduate student Rosalind Baynham, a bunch of healthy men drank a high-flavanol cocoa drink 90 minutes before finishing an eight-minute mental stress task.
The researchers measured forearm blood flow and cardiovascular disease activity at rest and during stress and evaluated functioning of the blood vessels up to 90 min post pressure – discovering that blood vessel function was impaired whenever the participants drank high-flavanol cocoa. The researchers also found that flavanols improve blood flow during stress.
Stress is highly prevalent in today’s society also continues to be linked with both physical and psychological health. Mental stress induces instantaneous increases in heart rate and blood pressure (BP) in healthy adults and results in temporary impairments at the function of arteries even after the episode of stress has ceased.
Single episodes of anxiety have been demonstrated to increase the risk of acute cardiovascular events and the effect of pressure on the blood vessels was suggested to bring about these stress-induced cardiovascular events. Indeed, previous study by Dr Jet Veldhuijzen van Zanten, co-investigator on this study, has demonstrated that people at risk for cardiovascular disease reveal weaker vascular responses to acute 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 high-flavanol 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,” commented Dr. Rendeiro.