Every body cell, tissue, organ and life sustaining body process needs water to function. By comparison, we can live without food for weeks. Younger people have more water than older people do. The percentage of body weight that is water gradually declines as we age. So how muchwater you have in your body partly depends on how old you are now.
Younger individuals tend to have more muscle than older people do.
Therefore, the leaner the individual the higher the waterproportion. Men, who on average have more lean tissue than women, have a higher percentage of water than women do. Water is also the most abundant nutrient in your diet. Drinking water and other liquids is the main source, but by no means the sole source. We eat a lot of water too.