According to several studies, seven hours is the optimal amount of time you should sleep.
Research has long shown that those who sleep between six and eight hours a day are less likely to develop a host of diseases – and even live longer.
But what about bedtime?
Surprisingly, recent research suggests that maintaining a consistent sleep routine could be more beneficial than staying asleep longer.
Dr. Chris Winter, neurologist, sleep expert and host of the Sleep disconnected Podcast told DailyMail.com that he recommends going to bed and waking up at the same time every morning.
“In general, sleep schedules are important because our bodies work best when they can anticipate what's coming, rather than simply reacting to it,” he says.
A study published last month found that going to bed at the same time every night reduced the risk of premature death by 20 percent
'Your body anticipates that everything else will happen at some point. So if that's always in flux, a lot of the things that happen as a result of sleep don't happen or aren't as effective because your brain isn't quite sure when it's coming.”
A study published last month in The sleep diary found that maintaining a regular sleep routine reduced the risk of premature death by 20 percent.
The researchers also noted that while the amount of sleep time was important, shorter, more regular sleep was associated with a lower risk of premature death than longer sleep with inconsistent bedtimes.
Dr. Winter uses the example of some shift workers who regularly alternate between day and night shifts, causing them to go to bed at inconsistent times.
However, people who consistently work night shifts are at a lower risk of health problems because their sleep routine is regular.
During the day, the body produces hormones such as cortisol, which regulates stress, and serotonin, which regulates mood.
In a healthy person, cortisol levels peak around 8am, waking us up, and drop to their lowest level at 3am the next day, before rising to their peak again five hours later.
Ideally, this 8 a.m. peak is caused by exposure to sunlight, if not by an alarm. When this happens, the adrenal glands and brain will start pumping adrenaline.
After midday, cortisol levels begin to decline steadily. Metabolism slows down and fatigue occurs. Gradually, serotonin turns into melatonin, which causes drowsiness.
Because sleep is always changing for shift workers, their bodies cannot properly regulate hormone production, resulting in poor sleep, difficulty concentrating, lack of energy and moodiness.
However, don't worry if you can't fall asleep at your scheduled bedtime.
'I think sometimes people get really worked up when they try to make their wake-up time or bedtime really strict because they can't fall asleep at that time. It's okay,” Dr. Winter said.
'The chance that you will go to bed at eleven o'clock every night for the next year and always fall asleep within five minutes is zero. If you go to bed at eleven o'clock tonight and you don't feel like you're falling asleep, I think the first thing you need to understand is that this is normal.'
And if you go to bed later one night, don't take a long nap to make up for it. This can make it harder to fall asleep at bedtime.
“Napping often perpetuates the sleep problem and turns an isolated, difficult night of falling asleep into something much more chronic and long-lasting,” says Dr. Winter.
The Sleep Foundation recommends winding down at the same time every night with a book, music or a warm bath to get the body used to a consistent routine.