Flavanols & Sitting: Protect Blood Vessels with Tea, Berries & Cocoa
Modern life is increasingly sedentary, and new research from the University of Birmingham suggests a dietary approach to mitigate the vascular health risks associated with prolonged sitting. The study, published in the Journal of Physiology, indicates that consuming foods rich in flavanols – naturally occurring compounds found in cocoa, tea, berries, apples, and nuts – may help protect blood vessels from the negative impacts of inactivity.
The Impact of Sitting on Vascular Health
Young adults are estimated to spend around six hours a day seated. Extended periods of sitting are known to reduce blood vessel function. Researchers have previously established that even a 1% decline in vascular function, measured by brachial Flow-mediated dilatation (FMD), correlates with a 13% increase in the risk of cardiovascular diseases like heart disease, stroke, and heart attack.
How Flavanols May Help
Flavanols are polyphenols with established links to cardiovascular benefits, including support for the vascular system during times of stress. The University of Birmingham researchers investigated whether increasing flavanol intake could counteract the vascular decline experienced during uninterrupted sitting.
The study involved forty healthy young men, divided into groups with higher and lower fitness levels. Participants consumed either a high-flavanol cocoa drink (695 mg of total flavanols) or a low-flavanol cocoa drink (5.6 mg of total flavanols) before a two-hour sitting session. Researchers then measured indicators of vascular health, including FMD in the arm and leg arteries, blood flow, blood pressure, and leg muscle oxygenation.
Key Findings of the Study
Those who consumed the low-flavanol drink experienced declines in FMD in both arm and leg arteries, alongside increases in diastolic blood pressure, reduced blood flow, and lower leg muscle oxygenation. Importantly, the study showed that existing fitness levels did not protect against these vascular effects.
However, participants who consumed the high-flavanol cocoa maintained their FMD levels throughout the two-hour sitting period. This is the first study to demonstrate flavanols’ ability to prevent sitting-induced vascular dysfunction in healthy young men. Dr. Sam Lucas, a co-author, explained that the high-flavanol drink allowed both fitter and less-fit participants to maintain their pre-sitting FMD levels.
Practical Implications
Researchers found that baseline cardiorespiratory fitness did not influence the body’s response to flavanol intake, suggesting potential benefits for individuals of all fitness levels. Alessio Daniele, a PhD student at the University of Birmingham, noted that incorporating flavanol-rich foods into one’s diet is relatively easy, citing readily available options like cocoa products, apples, plums, berries, nuts, and black and green tea.
Dr. Catarina Rendeiro emphasized that consuming high-flavanol foods and drinks during sedentary periods could lessen the impact of inactivity on the vascular system. She suggested combining this dietary approach with regular breaks for short walks or standing to further enhance long-term health.
Frequently Asked Questions
What are flavanols?
Flavanols are naturally occurring polyphenols found in various fruits, tea, nuts, and cocoa beans. They have previously been linked to cardiovascular benefits.
Does fitness level matter when it comes to the vascular effects of sitting?
The study showed that higher fitness levels do not prevent the temporary impairment of vascular function induced by sitting when consuming a low-flavanol drink.
How much flavanol was used in the study?
Participants consumed either a high-flavanol cocoa drink containing 695 mg of total flavanols or a low-flavanol cocoa drink containing 5.6 mg of total flavanols.
Could incorporating flavanol-rich foods into daily routines become a simple strategy for supporting vascular health in our increasingly sedentary world?