Have you ever been so exhausted that you can't wait to get into bed? You cancel all plans. You have a quiet night. You slather your face with a rich night cream, put on your jammies and prepare to say goodnight. You get into bed, and... you can't fall asleep. So what's wrong?

If you suffer from backache, it's better to rest on foam.

Everyone knows humans need sleep. Adults need on average just under eight hours of sleep per night for good brain function (although this varies from person to person, with some needing as little as 6.5 hours and some needing as many as 10). To find out why sleep is so important, I talked to Dr. Andrew Lim, neurologist.

Bring on the 2 a.m. to 7 a.m. sleeps.