While most of us experience a few sleepless nights from time to time, chronic sleep loss can be a major problem, contributing to a number of health problems, such as heart disease, stroke, obesity, diabetes, and depression.

Interestingly, Robert Stickgold, a Harvard psychiatrist and sleep researcher, referred to this state as "sleep bulimia," where we become sleep deprived and make up for the loss in one large block, such as during weekends.

The 2005 National Sleep Foundation survey...