Many people today spend hours sitting at desks, on the couch, or in cars. While this may feel relaxing, too much sitting can be harmful to our health—especially to our blood vessels.
A new study from the University of Birmingham has found that eating foods rich in flavanols, such as cocoa, tea, apples, and berries, may help protect men’s blood vessels during long periods of sitting.
Spending a lot of time sitting has been linked to poor blood flow and weaker blood vessel function. This can lead to serious problems like heart disease, strokes, and high blood pressure.
Even just a 1% drop in blood vessel function can increase the risk of heart disease by 13%. This new study wanted to see if what we eat—specifically flavanol-rich foods—could reduce some of the damage caused by sitting.
Flavanols are natural compounds found in certain plant-based foods. They are a type of polyphenol that supports heart and blood vessel health. Cocoa, tea, berries, apples, plums, and nuts are all good sources. These foods have been shown in earlier research to improve blood flow and reduce stress-related damage to the body.
The study was published in the Journal of Physiology. Researchers tested whether flavanols could help protect blood vessels when someone sits still for two hours. They recruited 40 healthy young men.
Half were physically fit, while the other half were less active. Each person drank either a high-flavanol cocoa drink or a low-flavanol cocoa drink before sitting for two hours.
To see how the body responded, scientists checked several things before and after the sitting period. These included how well blood flowed through the arm and leg arteries, blood pressure, and how much oxygen the leg muscles were getting.
Men who drank the low-flavanol cocoa showed signs of damage to their blood vessels after sitting. Blood flow decreased, diastolic blood pressure went up, and their leg muscles received less oxygen. These changes happened in both fit and less-fit men. Being more physically fit didn’t prevent these effects.
However, the men who drank the high-flavanol cocoa did not show any of these problems. Their blood flow remained normal, and their arteries continued to function well even after sitting. This suggests that flavanols helped protect their blood vessels.
The researchers also discovered that the benefits of flavanols were the same for both fit and unfit men. This means that even if you are not in great shape, eating foods with flavanols might still help protect your heart and blood vessels when sitting for long periods.
This was the first study to show that flavanols can directly prevent blood vessel problems caused by sitting. It highlights how something as simple as a healthy drink or snack could make a big difference, especially for people with desk jobs or long commutes.
Dr. Catarina Rendeiro, who led the study, explained that long hours of sitting may seem harmless but still cause stress on the body. Adding flavanol-rich foods to your daily meals—like cocoa, black or green tea, and fruits like apples and berries—can be an easy way to protect your health. Taking short breaks to stand or walk also helps.
The team hopes that future studies will include women to see if the benefits are similar. They avoided including women in this trial because hormones like estrogen may affect how flavanols work in the body. More research will help guide better health advice for everyone.
In the meantime, enjoying a cup of tea or a small piece of dark chocolate may do more than just taste good—it might actually keep your heart and blood vessels healthy, even when you’re stuck sitting.
If you care about nutrition, please read studies that vitamin D can help reduce inflammation, and vitamin K may lower your heart disease risk by a third.
For more health information, please see recent studies about foods that could sharp your brain, and results showing cooking food in this way may raise your risk of blindness.
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