The human body contains water everywhere, inside the cells, outside the cells, inside the blood vessels and outside the blood vessels. The water content in the human body is different for men and women, and also different for different age groups. For example, a baby weighing 10 kg contains 7.5 kg of water, of which 4.5 kg is in the cells, 0.4 kg in the blood plasma and 2.6 kg in the interstitial fluid. The water content in the body of adult men accounts for about 60% of their body weight, of which 40% is in the cells, 5% in the blood plasma and 15% in the interstitial fluid. The water content in the body of adult women is not more than that of men, but 10% lower than that of men, accounting for about 50% of body weight, of which 35% is in the cells, 4% in the plasma and 11% in the interstitial fluid.