1, from the brain function, after drinking a lot of water, the human body is easy to produce a feeling of fatigue, appetite is greatly reduced, the head feels drowsy. Doctors pointed out that this is because drinking too much water washed out the blood, the whole body cells of the oxygen exchange will be affected, brain cells once the lack of oxygen, people will become sluggish.

2, too much water will aggravate the heart, kidney burden, so heart disease, high blood pressure, kidney disease and edema can not be a large number of people can not drink a lot of labor or exercise and sweat should not drink too much.

3, excessive drinking but will lead to excessive loss of human salt, some water will be absorbed into the tissue cells, so that the cells edema. At the beginning, there will be dizziness, weakness, heartbeat and other symptoms, and in severe cases, there will even be spasms, impaired consciousness and coma, that is, water intoxication.

4, night because of fear of nocturnal urination caused by the kidney burden, to be appropriately reduced; before the meal when people in the hungry state because there is gastric acid secretion, drink too much will affect the concentration, affecting digestion.

5, drink too much water, so that the blood volume increased dramatically, the heart is working to increase the burden of the heart, have to carry out a strong contraction to compensate. And the kidneys in a short period of time to excrete more water, but also consume energy, repeated so work, the heart and kidneys will also be "fatigue", so that its function is reduced.