People burn more calories when awake.
People burn less calories while sleeping.
Person on average burns 83 calories per hour while awake.
But only 50 calories per hour while sleeping.
So if you sleep for 16 hours instead of 8, you can save up to 250 calories each day.
83 - 50 = 33 less calories per hour.
16 - 8 = 8 extra hours of sleep
8 x 33 = 264 calories saved
Science is so cool.