Ive always heard that 8 hours is the healthy and recommended amount of sleep you need every night. But I also think everyone is different. If I sleep more than like 6 hours, Its very hard for me to get up at all. So I think it depends on your daily routine and how active you are as to how much sleep YOU need. I hope this helps. =)
I've always heard 8 hours as well. I also feel like I have more energy and I am more awake when I go to bed later and get up early because your body doesn't have to go through the process of waking up out of the four stages of sleep. It also depends on age. Baby's need up to 16-18 hrs of sleep, while teenagers are supposed to need 9, and adults 7-8. Being in the army in basic training they were required to give the soldiers 5 hours of sleep and it didn't have to be consecutive and then we would end up working up to 19 hr days sometimes. It all depends on you and your lifestyle...but lack of sleep can cause your immune system to become weak and it's a lot easier to get sick. Here is a link I found pretty interesting: http://www.webmd.com/sleep-disorders/excessive-sleepiness-10/sleep-101?page=2
I've heard lots of people claim they do fine on 4-5 hours sleep then see them make constant mistakes all day. Try to get 8 hours, if you only get 5-6 one night then catch up the next night. Feeling more awake after lacking sleep does not mean its better, that's from body burning more energy to stay awake lacking sleep but your brain is performing worse just with more energy. Get the 8 hours.
The recommended amount of sleep for a human bein is around 8 hours. One true fact is that if you don't go to sleep before 9:00 your body starts storing fat because it thinks your going to starve it. also when you don't go to bed before 9:00 your body stores more fat for the next day because food is how you get your energy so your body wants to have enough food/energy to last for the next day.
From birth to around 5yrs you should get 12-16 hrs from 5-18 yrs 10 yrs is suggested, from 18 -70 yrs try to get 8-10 hours per night after the age of 70 the body tends to sleep less at night but people will doze off or nap during the day. Women also have problems maintaining sleep when estrogen begins to drop off during their late 40's into their 50's. Just because your in bed doesn't mean your getting a solid 8-10 hours per night. People tend to wake frequently without remembering it. They will be awakened by leg movements, snoring, obstructive sleep apnea and spousal movements and snoring. Thats why all of us should speak to our Doctors about sleep testing. I'm a Polysomnography Technician or Sleep Tech.
If you are a little child like at the age of 8 or 11 you need 10 or 9 hours of sleep! Teenagers need at least 7 or 8 hours of sleep! Grown ups need at least 6 or 7 it's bad for your brain if you don't have enough sleep.
it depends on how old you are as you get older you can function on less hours of sleep if you are a teenager 7 or 8 hours if you are an adult you can function on 6 to 7 hours give or take with caffeine
I encourage you to experiment and sleep with no alarm waking you, or other disturbances and see how long you sleep naturally. Most of us wake up naturally in increments of 90 minutes (an average sleep cycle) So, 8 hrs, while often recommended, falls in the middle of a sleep cycle. Multiples of 90 minutes; 6 hrs, 7 1/2 and 9 hours may be more suited to your bodies rhythm. More info here: http://www.lifehack.org/articles/lifehack/90-minutes-sleep-cycle.html
most of these answers are based just on a monophasic sleep cycle. really, all you need is stage four REM sleep. an alternative is to try a polyphasic sleep cycle, which aren't common, and are hard for your body to adjust to. but if you're willing to try, can be very beneficial. each polyphasic sleep cycle tricks your body into thinking there has been a lack of sleep, therefore your brain enters REM sleep immediately. technically, your body only needs about two hours of reparitive REM sleep. try looking up "alternative sleep cycles" or "uberman sleep cycle". you should get all of the polyphasic cycles from there. good luck!
Well it depends on how active you are throughout the day and on your age. For a healthy adult around the age of 30 only needs 6 hours of sleep a night. This if because at your healthy state, your body can heal faster. When you get older, like in your late 50's, 8 hours a night is what you will need. Because your body and mind are growing older and slower, so does the healing proses. A young adult needs more sleep as well because there growing so fast that there minds need more rest to play catch up. In all reality, everyone is different. Some people can get into the deeper parts of sleep faster and dont need to sleep that long and some need more sleep than others. You should try and stick with 8 hours. If you wake up still feeling tired, then you eather slept too long or not enough. Move it around an hour or too till you find your sweet spot where you wake up feeeling refreshed. Remember, Once you wake up, you are the one to decide its going to be a good or bad day. Say to yourself, Today is a good day and I wont let anyone ruin it for me.