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.

Turns out, sleeping more than six to eight hours a night is associated with an increased risk of death and cardiovascular diseases.

According to a recent study at the McMaster and Peking Union Medical College, people sleeping more than the recommended upper limit of eight hours increased their risk of major cardiovascular events, like stroke or heart failure, as well as death by up to 41 per cent.

But a possible reason for this could be that people have underlying conditions causing them to sleep longer, which in turn could raise the risk of cardiovascular disease or death, explained the authors of the study.

“Daytime napping was associated with increased risks of major cardiovascular events and deaths in those with [more than] six hours of nighttime sleep but not in those sleeping [less than] 6 hours a night,” said Chuangshi Wang, a researcher.

Dr. Tara Narula, medical contributor for CBS News, said that the study may be showing that people who are sleeping longer have underlying medical conditions, such as weaker immune systems and adverse behavior when it comes to their health.

Narula added that people should strive for consistent and regular sleeping patterns following a regimen every night to keep the body accustomed to a set amount of sleep.

How Many Hours Of Sleep Should You Get?

The study suggests that people should not be getting more than 9 hours of sleep each night, as each hour beyond that places them in the danger zone. The research actually coincides with a study carried out by scientists from the Seoul National University College of Medicine, which found that sleeping for more than 10 hours could lead to the development of heart disease.

On the other end of the spectrum, sleep deprivation also has several negative effects on a person’s health. People are recommended to get at least 7 hours of sleep each night to avoid diseases such as cancer, diabetes, Alzheimer’s disease, and more.

Dr. Daniel Gartenberg, however, further narrows the window by saying that people need to get at least 8.5 hours of sleep every night because the modern world is bombarding them with information.

As such, it appears that the sweet spot for sleep is between 8 hours to 9 hours, which is ideally what people should be getting every night.