Researchers from Harvard, MIT, and the University of Colorado have observed that people who wake up earlier tend to be less depressed.

Though the study has only been among European descendants, the study shows that going to sleep early and waking up an hour or two early lo...

We can remain in stage 4 - similar to a coma or brain death - for only about 30 minutes before the brain wakes up and falls back to sleep again. 

Even healthy sleepers wake several times a night, but might not be aware of it.

It is imperative to sleep 7 to 9 hours for most adults.

An alarm clock or phone alarm can interfere with the body's sleep cycle to wake us up before a cycle is completed. It is healthier to sleep while not being simulated and wake up naturally.