According to a new study of 250 patients from researchers in the Netherlands, coffee, sex and blowing your nose are among eight risk factors that could boost the risk of having a certain type of stroke. All of these actions increase blood pressure, and could result in blood vessels bursting, which can lead to brain damage or death, the BBC reports. Researchers looked at 250 patients for three years to find out what triggers these ruptures, and found that coffee was responsible for more than one in 10 brain aneurysms (when a weakened blood vessel bursts). Coffee increased the risk only 1.7 times, but it’s more common than the other risk factors. Being startled increased the risk by over 23 times, but it was responsible for less than 3 per cent of cases. One in 50 people have a brain aneurysm, they said, but only a few rupture.