ScienceDaily (2007-10-04) — A lower metabolism, as well as slight changes in eating behavior, could explain the positive energy balance leading to being overweight in narcolepsy. Narcolepsy is a sleep disorder that causes people to fall asleep uncontrollably during the day. It also includes features of dreaming that occur while awake. Other common symptoms include sleep paralysis, hallucinations and cataplexy.

http://www.sciencedaily.com/releases/2007/10/071001081647.htm