KHALED HOSSEINI

A healthy sleeper actually takes a couple of minutes to fall asleep. We do see that if people fall asleep right away, that can be a sign that they are not getting quite enough sleep.

It takes the healthy sleeper about 15 minutes to fall asleep, but much longer than that… make sure to get out of bed, change the environment and do something that's mindless.

• Everyone has occasional difficulty sleeping, but some people have Insomnia, a chronic problem with falling or staying asleep. Another kind of sleep disorder is Narcolepsy, which is a tendency to fall asleep periodically during the day. Narcolepsy can be dangerous, as people who experience it...