Study: Less sleep linked to weight gain.

The New York Times (3/19, Parker-Pope, 1.68M) "Well" health blog reports sleep researchers from the University of Colorado found that "losing just a few hours of sleep a few nights in a row can lead to almost immediate weight gain." In an experiment, the researchers "found that staying up late and getting just five hours of sleep increased a person's metabolism," but "light sleepers ended up eating far more than those who got nine hours of sleep, and by the end of the first week" of the experiment, "the sleep-deprived subjects had gained an average of about two pounds." The blog explains "the researchers found that insufficient sleep changed the timing of a person's internal clock, and that in turn appeared to influence the changes in eating habits."