Under normal circumstances people drink 2500mL of water a day is enough, if in the hot summer or labor intensity is relatively high, resulting in more sweating, the need for fluid will increase. If suffering from a cold and fever, the body needs more water because of metabolism, the amount of water can be increased to about 4000mL. In addition, drinking 2500mL of water is also delicate, not a one-time drink, usually each time the amount of about 250mL can be, each interval of 2-3 hours, it is best to drink this amount of water before 10 pm, because after 10 pm to drink in, this time the body water metabolism is slower, which will easily lead to edema symptoms the next day.