[User23]

Getting sufficient sleep is on the same level of importance for overall health as proper exercise and nutrition.

Among other things, sleep is when the majority of most people's fat loss occurs, because the body is in a fasted state, oxidizing lipids for basal energy needs, and expelling the resultant Carbon Dioxide and water.

There are a great many other metabolic systems in the body that are detrimentally affected by a lack of sleep too. It's quite important to get enough!