Scientists at the University of Southampton in the United Kingdom have figured out why sunlight can lower your blood pressure. Their findings call into question the assumption that people should spend as much time out of the sun as possible in order to avoid skin cancer.
The Southampton researchers determined that the chemical nitric oxide, which is located in the upper layers of your skin, reacts to ultraviolet light and causes blood vessels to widen. This relieves pressure and results in better blood flow. While the effect is mild in those who have normal blood pressure, the scientists have said that they believe the effect could be more pronounced in those who are already disposed to have higher levels.
"This is an unexpected finding, in that the skin has not been considered to be involved in blood pressure regulation," Martin Feelisch, the lead researcher and a professor of experimental medicine and integrative biology at the University of Southampton, said in a press release. "This is a mild effect. But if you repeat this study in people with high blood pressure, I would predict you will see a more substantial drop."
Feelisch believes that those with higher blood pressure should think green and spend some time outside during the day, though he advised against flat out sunbathing and spending too much time in direct sunlight. But the next time you're feeling stressed out and think your blood pressure may be getting out of control, try heading outside, visiting a local outdoor farmer's market and catching a few rays to relieve the stress and open up your blood vessels!