Too Much Sleep Is So Bad For Your Health It Could Kill You

A study of more than 116,000 people has found too much sleep could be linked to a greater risk of cardiovascular disease and even death.

What you need to know
  • Six-eight hours of sleep per night recommended for adults
  • Study finds too much sleep linked to heart problems
  • Those sleeping 10+hours have 41 percent increased risk of disease

It's something we're told time and time again - get enough sleep. Now new research suggests there's a big difference between 'enough' and 'too much'.

An international study tracking 116,632 people from 21 countries for nearly eight years, found spending too long in bed can be linked to an increased risk of cardiovascular disease and even death.

And the longer you sleep, the greater the risk.

Compared to the recommended six-eight hours each night, people who slept 9-10 hours had an increased risk of 17 percent. While those who really loved a snooze and slept for more than ten hours a day had a whopping 41 percent increased risk.

READ MORE: None Of Us Are Getting Enough Sleep And Here's How To Fix It

"Risk of mortality was significantly higher in those with longer sleep durations, and high (but not statistically significant) in those with shorter sleep durations," the study published in the European Heart Journal found.

Photo: Getty

"Our study shows that the optimal duration of estimated sleep is six to eight hours per day for adults," lead author, PhD student Chuanghshi Wang from the Chinese Academy of Medical Sciences said.

There's more bad news - napping may not be the best either.

"People who slept six or fewer hours at night, but took a daytime nap, and so slept an average of 6.4 hours a day in total, had a slightly increased risk compared to those who slept between six and eight hours at night without a daytime nap, but this finding was not statistically significant," the study concluded.

Before you start timing your sleep to the minute, a better idea may be to visit the GP for a check up. Researchers warn the duration of your zzzz's may not be the cause of a health problem - instead a sign of one.

READ MORE: The Sleep 'Sweet Spot' To Reduce Heart Problems

“Given that this is an observational study that can only show an association rather than proving a causal relationship, we cannot say that too much sleep per se causes cardiovascular diseases," Ms Wang said.

"Too much sleep may indicate underlying conditions that increase risk."

It's important to note it's not a one size fits all approach and more than ten hours sleep can be healthy for children.

The amount of sleep a person needs tend to decrease as they age, before evening out around the age of 20, according to the Australian Sleep Health Foundation.

It’s recommended children under the age of 13 sleep between nine to 12 hours per day, while toddlers can sleep up to 14 hours.