Experts Figure Out Exactly How Much Sleep You Need

Feeling so tired today? Perhaps last night's amount of shut-eye didn't jibe with the National Sleep Foundation's updated recommendations. In a newly published report in Sleep Health, the nonprofit foundation sets its objective: "to conduct a scientifically rigorous update to the [its] sleep duration recommendations," a task it undertook with the help of an 18-member multidisciplinary expert panel who pored over more than 300 studies on the subject. The recommendations, with USA Today's notations on which categories are new, and which saw adjustments:

• Newborn (0-3 months): 14-17 hours (was 12-18)
• Infant (4-11 months): 12-15 hours (was 14-15)
• Toddler (1-2 years): 11-14 hours (was 12-14)
• Pre-school (3-5 years): 10-13 hours (was 11-13)
• School age (6-13 years): 9-11 hours (was 10-11)
• Teen (14-17 years): 8-10 hours (was 8.5-9.5)
• Young adult (18-25 years): 7-9 hours (new)
• Adult (26-64 years): 7-9 hours (same)
• Older adult (65+ years): 7-8 hours (new)

The CDC last year called insufficient sleep a "public health epidemic," and noted that an estimated 50 million to 70 million adults suffer from sleep or wakefulness disorder. On the subject of sleep: 6 reasons to sleep naked. (More sleep stories.)