Here are their recommended sleep times:
- Zero to three months of age: 14 to 17 hours
- Four to 11 months of age: 12 to 15 hours
- One to two years of age: 11 to 14 hours
- Three to five years of age: 10 to 13 hours
- Six to 13 years of age: nine to 11 hours
- 14 to 17 years of age: eight to 10 hours
- 18 to 25 years of age: seven to nine hours
- 26 to 64 years of age: seven to nine hours
- 65 and older: seven to eight hours
By comparison, the National Institutes of Health recommends that newborns sleep 16 to 18 hours; preschoolers sleep 11 to 12 hours; school-aged children sleep at least 10 hours; teenagers sleep nine to 10 hours; and adults, including the elderly, sleep seven to eight hours.
"Sleeping too little and too much are both associated with increased risk of mortality and a range of other adverse health issues: cardiovascular disease, possibly cancer and also impaired psychological well-being," said Lauren Hale, editor of the journal Sleep Health and associate professor of preventative medicine at Stony Brook University.
The National Sleep Foundation convened an 18-member panel of sleep experts and people representing 12 different professional health organizations, including the American Academy of Pediatrics, the American Geriatrics Society and the American Psychiatric Association.
This panel studied 312 peer-reviewed articles published between 2004 and 2014 that dealt with sleep duration and the effects of too little or too much sleep. Panel members met four times over a nine-month period and voted twice to come up with the recommended numbers.
The scope of the results and the methodology behind them make the recommendations a first, Hale said.
"The National Sleep Foundation felt it was the time and their role to assemble this panel, and they've been working on it for years," Hale said. "There has been a shortage of scientific expert panels on the topic of sleep duration... We just know it's one of the questions that people ask regularly. People type those questions into Google all the time, and there wasn't a consensus."
The foundation had previously posted recommendations on its Web site, but they were "a bit dated" and weren't developed following the same kind of thorough literature review and input from various professional organizations as the new guidelines, a spokesperson said. In some cases, the previous recommendations included wider hour ranges or more narrow ones. And new categories were added for younger and older adults.
The new recommendations also include "may be appropriate" hour ranges, which can be seen below:
As for how much people are actually sleeping, the data are kind of all over the place. You could look to the Bureau of Labor Statistics, which says the average American over the age of 15 sleeps eight hours and 45 minutes. Or, you could turn to a 2013 Gallup poll in which the average American reported sleeping 6.8 hours nightly.
The Centers for Disease Control and Prevention has called insufficient sleep a public health epidemic. And Hale, who focuses on teenagers, said most American teens are simply not sleeping enough on a whole.
Hale said that while every individual is a little different, the recommendations can provide guidance for parents and others in creating household environments conducive to children and adults alike getting enough sleep (think: electronics off and lights out). And if people are sleeping over the recommended range, this may be a signal of other health problems, such as depression.
"There are always exceptions, whether it's a flight to catch, a test to take, things to do, and some days you need to sleep over the range because you are sick," Hale said. "But, on a regular basis, you should try to aim for the recommended range."
[This post has been updated.]