There are 2 stages of sleep; 1. non-REM (which has 1, 2, and slow wave stages) and 2. REM. Just to keep it simple, they are all important for different reasons.

Over 50% of our gene regulation is governed by our circadian rhythm, i.e. our light/dark cycle that occurs each day. Since we spend 90% of our lives indoors these days our brain and body get confused, especially with our exposure to light at night and just before bed.

…but let’s dive quickly into weight first. 

– If you sleep less than 6 hours per night your chances of obesity increase by 60%!
– poor sleep increases desire for pleasurable foods (usually not the healthy choice)
– poor sleep decreases Leptin levels (hormone that tells brain how much fat is stored) and increases Ghrelin levels (hormone that makes your hungry), increasing your risk of weight gain and diabetes

– chronic poor sleep is said to put people at a 4 fold increase for developing Cancer.
– mice exposed to light at night became resistant to chemotherapy treatment
– melatonin regulates genes for angiogenesis, the process that gives tumors blood supply for growth.
– blind people produce more melatonin (not disturbed by light) and have less chance of getting cancer.

– a build up of a protein called beta-amyloid is thought to be responsible for this disease, and is has been shown to be cleaned from brain neurons during sleep. 

– poor sleep can actually cause brain atrophy (shrinkage) in mice
– a part of your brain called the hippocampus stores learning during the day – at night when sleeping that information replays in the mid pre-frontal cortex so that it can become a memory. Poor sleep = poor memory.

– the part of our brain that is responsible for fear is called the amygdala. when it is active it turns on aspects of it’s function that should only be active during the day. 

– possibly the underlying cause of many diseases. antioxidants are substances that regulate inflammation and the damage it causes. antioxidant enzyme genes are turned on when we sleep. less sleep = more inflammation.

– the friendly bacteria in our guts work in concert with our circadian rhythms as well. simply put, don’t eat late at night or you throw your digestion into chaos.
– DHA (omega oil) and magnesium from our diet convert serotonin to melatonin, so proper digestion of these essential substances supports good sleep.

– EXERCISE – there is nothing more important than physical activity.
– LIGHT EXPOSURE – connect to the sun during the day (go outside) enjoy the sunrise and sunset so that your ‘wake’ and ‘sleep’ rhythm kicks in. think about it this way – too much light at night and not enough during the day will make you walk through life with mini ‘jet-lag’ syndrome. also, minimize blue light exposure before bed (shut off the screens or get some blue light glasses).
– DURATION – depends on need (busy, intense exercise, travel etc) but shooting for 8 hours is about right. Ideally, what is right for you is when your body wakes naturally from an approx 8 hour slumber (without the alarm clock). So, go to bed early enough so that you wake in plenty of time to start your day, naturally.
– TIMING – go to bed with respect to your circadian clock, not too late, and go to bed the same time each night.

Go get some good sleep – your life (and most likely fertility) depends on it.

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