- by foxnews
- 04 Apr 2026
A new study from the University of Birmingham found that eating foods rich in flavanols - natural compounds found in cocoa, berries, apples, tea and nuts - can help protect blood vessels from the harmful effects of prolonged sitting, which can induce declines in vascular function and is linked to higher risks of stroke, heart attack and cardiovascular disease.
Experts have known that flavanols, a type of polyphenol compound that occurs naturally in some fruits, tea, nuts and cocoa beans, have been shown to have cardiovascular health benefits, so they set out to see if they could stave off the harms of prolonged sitting, too.
"Whether we are sitting at desks, behind the wheel of a car, on a train, or on the sofa reading a book or watching TV, we all spend a lot of time seated," lead author Catarina Rendeiro, Ph.D., assistant professor of nutritional sciences at the University of Birmingham, said in a news release. "Even though we are not moving our bodies, we are still putting them under stress."
A mere 1% reduction in vascular function can lead to a 13% increased risk of cardiovascular disease, previous research has found.
Forty healthy young men - half highly fit and half less fit - drank either a high-flavanol cocoa beverage or a low-flavanol version before completing the sitting trial.
Before and after the sitting session, researchers checked how well the men's blood vessels were working, looking at things like how flexible their arteries were, how much blood was flowing through them, their blood pressure and how much oxygen was getting to their leg muscles.
Regardless of fitness level, men who drank the low-flavanol cocoa drinks experienced declines in blood vessel elasticity in both the arms and legs, along with higher diastolic blood pressure, reduced blood flow and lower muscle oxygenation.
But men who consumed the high-flavanol cocoa did not show any of these declines, suggesting that flavanols can prevent sitting-induced vascular dysfunction. The researchers said that the study included only men because hormonal shifts during the menstrual cycle could affect vascular responses, and should be examined in future research.
The researchers said that eating flavanol-rich foods during long periods of sitting may help reduce some of the strain inactivity puts on the blood vessels, and noted that these foods are easy to add to the diet through everyday items like apples, berries, nuts and tea.
The researchers noted additional limitations, including that participants' fitness levels and diets weren't fully captured and that polyphenols from earlier meals may still have been present. They added that future studies should better account for sports backgrounds, more detailed diet tracking, and longer restrictions on polyphenol intake before testing.
Multiple trials have shown that cocoa flavanols can improve blood vessel function, though their impact on real-world cardiovascular risk appears modest and still developing. The Birmingham study also explored new ground and few studies have tested whether nutrients can help counteract the vascular strain caused by prolonged sitting.
The research was supported by the College of Life and Environmental Sciences at the University of Birmingham.
Fox News Digital has reached out to the study authors for comment.
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