Whether you're an early bird or a night owl can actually say a lot about your health.
The preference for morning or night is known as your sleep chronotype and it can affect your waistline, pain tolerance and even your personality.
Researchers studied 200 people and their sleep habits and found that early birds usually feel more tired.
Our bodies have a system that is build up of feelings of sleepiness throughout the day, and in early birds it builds up faster.
If you're a night owl, you probably have more of an appetite and indulge in a midnight snack.
One study found early risers only ate 299 calories after 8 p.m. while night owls ate 677 calories.
Owls are also more likely to snore and also have poorer memory.
There are four REM phases of sleep and since owls usually get less sleep, they lose the fourth stage of dreaming sleep, which may affect memory.
More bad news for owls: they feel more pain.
People deprived of the fourth stage are more sensitive to pain the next day.
But, owls have more fun.
Evening types tend to be more outgoing and take more risks.
Early birds are better at controlling impulse and are more agreeable.
What if you're an early bird and your spouse is a night owl?
It turns out it's good for your marriage.
Evidence shows some of the longest surviving marriages are between morning people and night people.
The reason? If you can accommodate your partner's sleeping habits, it shows a true give and take in the relationship.
If you're a night owl now, that may change in a few years.
As we get older, we tend to wake up earlier and earlier--as early as 4 a.m.
If that's too early for you, drink cup a coffee at night to help you stay up until midnight.
After a week, you should be waking up at 6 a.m. instead of 4 a.m.