For your blood pressure: Get 20 minutes of daylight a day. That doesn’t mean baking in the sun… you can get enough UVA rays walking the dog – or sitting by a window to drink your morning coffee. According to the Journal of Investigative Dermatology, people getting 20 minutes of daylight saw their blood pressure drop 2 points without changing anything else. The reason? UVA light helps nitric oxide circulate in your blood. And that regulates blood pressure and lowers your risk of stroke.