On body fat and body water in rats.

Under our experimental conditions, water represented 72% of the fat-free body mass. This constant was found to be completely independent of the magnitude of the fat depots. Consideration of the composition of various samples of adipose tissue suggests that the water to fat-free dry matter ratio is the same as in the body as a whole or that any "excess" water contributed by adipose tissue is so small in absolute amounts as to leave the global ratio essentially undisturbed. Rats exposed to cold had to draw on their fat stores during the first month of exposure but later replenished their energy reserves. The water to fat-free dry matter ratio was not affected.