Conventional wisdom holds that adults need eight hours of sleep a night to wake up feeling healthy and rested. But like many pieces of old advice, scientific investigation has found that this guideline isn’t as simple as we might think. Now, new sleep guidelines from some of the top experts in the field attempt to answer the ultimate question: How much sleep do you really need? 
New Guidelines for Recommended Sleep Hours
Recently the National Sleep Foundation released a new set of updated recommendations for sleep duration for each age group. The findings of their research are displayed in the graph above.
Required sleep duration changes based on a number of different factors. Clearly the most significant component is age. Newborns spend up to 2/3 of thier time sleeping, with a recommended 14-17 hours per day. Infants (older than three months) should get 12-15 hours. Toddlers should get 11-14 hours, preschoolers need 10-13, and school age children should get between 9 and 11 hours of sleep every night.
Once humans hit school age their sleep needs even out slightly. From school age (8-10 hours a night) to older adult (7-8 hours a night) there is a slow but gradual reduction in required sleep.
Are These Rules Absolute?
You’ll notice that each age group is paired with a range of possible sleep times. In fact, it may be appropriate for adults to get anywhere from 6 to 10 hours of sleep per night! This is because everyone’s health is different. Some people can operate with a lighter sleep schedule, while others require a lot of time in bed to recharge.
Ultimately, your body will tell you if you’re getting the sleep you need. If you dread getting up in the morning, need your alarm clock to prod you out of bed, feel slow or drowsy during the day, need your caffeine to keep you going, or tend to sleep long hours on the weekend, those are all signs that you might need to spend more time napping.
What If I’m Really Outside The Parameters?
If you’re getting significantly more or less sleep than what’s recommended, or you do sleep the required amount but you still feel fatigued during the day, it might be time to change your sleep schedule or talk to a doctor. It may be necessary have a sleep study or other tests done to try to figure out why it is you need so much or so little sleep. Changes in diet, sleep schedule, or even medication might be necessary to help you bring yourself in line with the hours you should be clocking.
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