A sleep study out of Western, the largest of its kind, says that the ideal amount of sleep is between 7 and 8 hours, and any more may be harming your brain.

The study included roughly 40,000 people from around the world with the majority from Canada, UK, USA, and Portugal.

The study found that those who sleep between 7-8 hours per night had better cognitive responses than those with more or less sleep.

The study concludes that sleeping too long is almost as bad as not getting enough sleep. Most respondents were getting less than the optimal amount with an average of 6.4 hours per night.

The study also debunked the theory that people need less sleep as they age.

Seniors who got the optimal amount of sleep performed better cognitively than those getting more or less.