[Sidenote: Proportion of water and solids in the human body]
Water, which forms about sixty-six per cent of the human body, is by far
the most important substance therein. It comprises the major part of the
blood serum and every tissue and organ. If a normal human body weighing
150 pounds were put into an oven and thoroughly dried, there would be
left only about 50 pounds of solid matter, all the rest being water.
The proportion of water in animal and vegetable substances is also very
great. As water is also a conspicuous factor in all foods, either in
chemical combination, or in solution with other elements mechanically
mixed, it is obvious that water is an important factor in food science.