It would seem that the belief that you should be asleep when you are awake, or the desire to fall asleep causes more stress, and therefore does more harm, than being awake and having full body rest.
Because sleep is not fully understood, no one really knows the full effect that insomnia has on the human body. The immune system seems to need sleep, and so does the production of human growth hormone, but it seems that for much of the physical body, simply lying down on a bed is just as good for restoring and repairing as actually falling asleep.
The brain’s need for sleep seems to be stronger because when a person lacks sleep, this is the part of the body that is mostly affected in a negative way.
The effects of constantly feeling tired and battling with sleep each night seems to make the rest of your life harder to cope with because it is harder to concentrate, remember things, and to work out problems. People are more emotional and likely to make snap decisions that they later regret when they are tired.
Perhaps the biggest effect that insomnia has on people is the craving for sleep that lurks just below the surface. The sneaking off to bed as early as possible, napping on the sofa, and spending eight to ten hours in bed at a stretch whenever possible.
Some people have the opposite effect; sleep is so irksome that they would rather work, or stay up as late as they can, in the belief that if they are really tired, sleep will be sounder.