Why a good snooze is a smart health move.

Quality sleep helps rejuvenate the mind and body. Here are few of its many benefits.

Sleep reduces disease risk.
With enough sleep, levels of the hormones melatonin and cortisol stay in healthy ranges. When cortisol is in check, it can prohibit the cell damage that can lead to cancers. While you're off in dreamland, chemicals called "immune system modulators" increase to help the body fight off potential infections, so it makes sense that sleep protects you from common illnesses like colds and flu. This is due to cortisol, since high levels of the hormone are associated with poorer immune function.

Sleep boosts brainpower.
A study from the University of Luebeck in Germany found that out of 106 people observed, those who obtained a full night's rest were three times more likely than sleep-deprived subjects to perform well on cognitive tasks measuring memory, creativity, and problem-solving skills. This is due to the brain activity that occurs during certain segments of sleep.

Sleep maintains your weight.
A joint study of more than 1,000 participants performed by University of Wisconsin and Stanford University researchers found that those who slept an average of eight hours a night had a lower body mass index (BMI) than those who slept less. Researchers believe that this is because sleep keeps two appetite-regulating hormones (leptin, which signals fullness and decreases with lack of sleep, and ghrelin, which stimulates the feeling of hunger and increases when you're lacking in sleep) in check. When they're in the right range, you're less likely to overeat.

Kristyn Kusek is a freelance writer based in Durham, North Carolina. Her work has appeared in the New York Times and More.