Although many scientists claim that people need at least eight hours of rest to support a healthy life, a new study led by the University of California, San Francisco (UCSF) has found that sleep quality appears to be more important than quantity.
According to the scientists, some “elite sleepers” are gifted with genes that allow them to get sufficient rest with only four or six hours of sleep per night. Moreover, these people often show psychological resilience and resistance to various neurodegenerative conditions.
“There’s a dogma in the field that everyone needs eight hours of sleep, but our work to date confirms that the amount of sleep people need differs based on genetics,” said study senior author Louis Ptacek, a neurologist at UCSF. “Think of it as analogous to height; there’s no perfect amount of height, each person is different. We’ve shown that the case is similar for sleep.”
For more than a decade, Dr. Ptacek and his colleagues have studied people with “Familial Natural Short Sleep” (FNSS) – the ability to function fully on only four to six hours of sleep a night. They discovered that this capacity usually runs in families and, until now, they have identified five genes that play a fundamental role in enabling this highly efficient form of sleep.
In order to assess the potential resilience of people with FNSS against neurodegenerative disease, the researchers bred mice that had both the short-sleep genes and genes that predisposed them to Alzheimer’s disease, and found that their brains developed much less of the hallmark aggregates typically associated with dementia. The scientists believe that these efficient-sleep genes may also offer protection against other neurodegenerative conditions.
A better understanding of the biological underpinnings of sleep regulation could help scientists identify drugs that could help ward off sleeping disorders, and thus improve health and well-being.
“Every mutation we find is another piece,” said Dr. Ptacek. “Right now we’re working on the edges and the corners, to get to that place where it’s easier to put the pieces together and where the picture really starts to emerge.”
“This work opens the door to a new understanding of how to delay and possibly prevent a lot of diseases,” added study co-senior author Ying-Hui Fu, a neuroscientist at UCSF. “Our goal really is to help everyone live healthier and longer through getting optimum sleep.”
The study is published in the journal iScience.