average percentage of water in the body
The average human body is estimated to be about 60 to 70 percent water. The percentage may be as high as 75% in infants, decreasing to 57-60% in adults. This does not include water that is part of hydrated chemical compounds in the body, which can only be removed chemically or by heat drying.
By weight, the average human adult male is approximately 70% water. There can be considerable variation in body water percentage based on a number of factors like age, health, weight, and sex. In a large study of adults of all ages and both sexes, the adult human body averaged ~65% water.