It’s well known that sleeping too little is bad for your health, but a new study published in the Journal of the American Heart Association has shown that getting too much sleep can also be risky.

Researchers reviewed data from 74 studies involving 3 million people and suggested that excessive sleeping may be a “marker” for poor health. Sleeping for more than 10 hours indicated a higher risk of dying from a stroke (a 56 percent increase) or cardiovascular disease (49 percent).

People who slept for more than 10 hours a night were 30 percent more likely to die prematurely than those who slept for eight hours.