An extra hour's sleep could be deadly
1 March 2002
US researchers say sleeping for 7 hours a night, and not 8, is ideal.
When they looked at the sleeping habits of more than 1.1 million adults, researchers found the lowest rate of death in people who slept for 7 hours a night (Archives of General Psychiatry, 2002;59:131-36).
People who slept more than 8.5 hours a night had 15 per cent greater mortality rates than those sleeping 7 hours. But the researchers could not say why mortality rates continued to increase the longer a person slept, or if reducing sleep would increase the lifespan of a person who slept for longer.
The study also showed that the mortality rate of those sleeping less than 3.5 to 4.5 hours a night was also increased by 15 per cent.
However, the death rate associated with the use of sleeping pills was greater than any risk associated with insomnia, which didn't appear to increase mortality, the researchers said.
Last Reviewed: 04 March 2002
- 1. Arch Gen Psychiatry, 2002; 59: 131-36.
