Dreaming can release fatigue and adjust body condition. Fatigue is the depletion of energy after physical and mental activity, the brain's blood supply depends primarily on the energy of glucose. Physical and mental activities require a lot of glucose, if glucose from the blood supply can not meet its needs, this time it will use the body's reserves. In the process of using body reserves, it will produce a lactic acid. More accumulation of lactic acid is the physical, biochemical performance of fatigue. Sleep can tie this fatigue. When falling asleep, all human activity ceased, the muscle also reduced consumption, for energy conservation, temperature is also reduced.

When people falling asleep, there is also a function that is synthesis of new proteins. Most new protein required for the body are synthesis during sleeping. Therefore, sleep is essential to rest the body and release fatigue.

Dreaming can organize information, to bring insight. We have experienced many things during the day, our brain record what is happening around you from time to time. When you sleep, the brain will play and organize information, and then depending on the content of the information, it will put it in different functional circuits of the brain respectively.

Dreaming can adjust psychological condition. We know that if have a good dream last night; we will feel energetic and very comfortable the next day. But if we have a nightmare, we will feel anxiety, irritability, angry, and can not do things quietly. So dream is an essential link to maintain a good attitude.

From the perspective of psychoanalysis, the meaning of dreams to satisfies desires. Whether you are a noble people, or a humble people, in our deep minds, there are a collection of desires that willing or able to say or unwilling or unable to say. These endless desires, many in real life can not come true or simply can not be satisfied. These unsatisfied desires can get psychological satisfaction in the dream, regulating psychological balance.

If you do not dream, then the desire for large and small will not allow us to sleep by. Even if we sometimes feel uneasy and anxiety in a dream, dream is always a good thing for body health.