Sleeping longer doesn't necessarily mean you're sleeping well,' the president of the American Academy of Sleep Medicine said. You've likely heard that not getting enough sleep can be detrimental to your health, but that doesn't mean sleeping for too long is good for you either. People who get too little sleep (six hours or less) or too much shut-eye (10 hours or more) are more likely to have coronary heart disease, stroke and diabetes, a new study from the Centers for Disease Control and Prevention suggests. Adults, especially those with chronic conditions, should aim for seven to nine hours of sleep a night, according to the American Academy of Sleep Medicine. "Sleeping longer doesn't necessarily mean you're sleeping well," Dr. M. Safwan Badr, president of the AASM, said in a release. "It is important to understand that both the quality and quantity of sleep impact your health." When it comes to sleep, can you have too much of a good thing? It's true a good night's sleep is essential for health. But oversleeping has been linked to a host of medical problems, including diabetes, heart disease, and increased risk of death. Researchers are careful to note, however, that two other factors -- depression and low socioeconomic status -- are strongly associated with oversleeping. Those two factors may be the reason for the observed negative health effects. For example, people of lower socioeconomic status may have less access to health care and therefore more undiagnosed illnesses, such as heart disease, which, in turn, may cause oversleeping.