You don't necessarily need the same amount as your best friend.
There is good reason for the old adage “sweet sleep.” Getting enough zzz's boosts your mood, improves your health, and makes you more productive at work, among other things.
How Much Sleep Do We Really Need
So what’s the magic number when it comes to the amount of time that’s ideal to spend in the sack? Well, there's unfortunately no one-size-fits-all number. It depends on your genes, how healthy you are, and how active you are during the day, among other factors.
Yet, for most adults, getting between seven and nine hours a night is the sweet spot to ward off daytime sleepiness and feel healthy. (If you can’t clock a solid seven hours overnight and feel sleepy during the day, try supplementing your nighttime sleep with a daytime nap.) As you age, however, your sleep needs do decline slightly -- after age 65, you will likely need between seven and eight hours nightly.
To pinpoint exactly how much shuteye works best for your individual needs, give yourself a week to sleep without an alarm clock, such as when you’re on vacation. You’ll begin to notice exactly how many hours of sleep you need each night after a few days— once you've made up for any sleep debt that you've accumulated. Once you know your personal magic number, you may be able to kiss your alarm clock goodbye for good—and feel refreshed each morning.