Narrator: This is Science Today. As a society, we tend to operate in overdrive Ė working long hours and juggling family or leisure activities. In the process, many of us are sleep deprived Ė or at least, thatís what we think. According to sleep expert, Daniel Kripke of the University of California, San Diego, it turns out that people who sleep eight hours or more have a higher risk of death from heart disease, stroke and cancer, than those who sleep seven hours or less.
Kripke: I wish we knew what the reason is, we really donít. It might be that something that causes long sleep also causes deaths, but itís independent of the long sleep. So itís important to understand that we donít know that a long sleeper will live longer if they shorten their sleep or set the alarm clock earlier. What we can say is that there doesnít seem to be any risk of their shortening their time in bed.
For Science Today, Iím Larissa Branin.