If you don't feel alert and awake after 12 hours of sleep you might be getting too much. When you either don't get enough sleep or get too much sleep you can feel groggy the next day and the cycle is likely to continue. Most individuals after sleeping long hours feel tired and groggy all day so they go to bed at 10 p.m. and sleep for another 12 hours.

Either way, a messed up sleeping pattern can affect your health. Experts for decades have been warning about not getting enough sleep. They have warned that not getting enough sleep can put you into a type of drunken state. In this state individuals are incapable of making decisions and have a higher chance of getting into car accidents and dying earlier.

It seems that nowadays few people are getting the recommended amount of sleep during the week so they try to catch up on weekends. It's fine to do this but usually it doesn't make the person feel a whole lot better. Now if you're on the opposite side of the spectrum and you sleep for longer periods you don't need to start panicking yet but experts are also starting to warn about oversleeping.

Experts recommend that individuals sleep between 7 – 8 hours per night. If you're spending that much time sleeping its important to understand sleeping. The average sleep cycle is 90 minutes. It begins with stage 1 the lightest sleep and then goes through progressively deeper sleep levels through stage 4. Then it continues with rapid eye movement (REM) sleep while the person is dreaming.

Now if you sleep a lot it could be a result of the poor quality you are getting. Having a crappy night of sleep will make you want to sleep longer because you spent most of the night in the first stage. But if you consistently sleep over nine hours on a regular basis and the quality is fine then you may want to see a doctor. Sleeping a lot can be a sign of serious health risks like sleep apnea, narcolepsy or restless legs form of sleep disorder and not even know it.

Sleeping is essential for our bodies and it's important to get the right amount. Studies have shown that if you get less than five hours of sleep or more than 10, it increases your mortality. A 2007 Finnish study showed that mortality risks increased by almost 20 percent for individuals sleeping more than eight hours. Another study showed people getting more than eight hours a night are at greater risk of a stroke than others that sleep less.

Experts also believe that when it comes to sleeping it's partly genetic. A study in the Journal of Science identified a mutated gene in a mother-daughter pair that allowed them to fully function on six hours of sleep. Experts believe this gene regulates sleep length.

Scientists have yet to fully understand why some people require more sleep than others, but believe genetics plays a role. For optimal sleeping experts recommend 7 – 8 hours and warn against not getting enough sleep and oversleeping, because they increase your mortality.