Feeling grumpy? You must have woken up on the wrong side of the bed.

The Huffington Post reports there's actually an explanation behind that saying. According to a new study, that wrong side of the bed is apparently the right side.

A survey published by the bed manufacturing firm Sealy UK found out that sleeping on the left side of the mattress brings a better start on your day. After asking about 1,000 people, the researchers were able to find out the effect this sleeping habit on people's moods, careers and outlook on life.

Results show that those who usually slept on the left side were 8% more likely to have many friends and enjoy their jobs. 4% were more likely to wake up in a good mood and 9.5% were more inclined to have a better outlook on life.

Meanwhile, those who slept on the right side of the bed were 9% more aloof, 7% more inclined to wake up in a bad mood, 3% more likely to hate their jobs and 5% more pessimistic.

Aside from being on the correct side of the bed, there are a lot more factors in sleep that could affect a person's mood when they wake up. On top of those factors is the amount of sleep the person gets.

"What we know is that if people don't get as much sleep as they should, they have changes in their mood and their level of activity," said Ana Krieger, MD, director of the New York University Sleep Disorders Center in New York City. "Adults just get moody and upset with everybody."

Considering the fact that sleep has "a huge effect on our personality and well-being", Krieger adds "everyone has an individual need to sleep."

"If you are not able to meet your needs, you are not going to behave."