The Utilization of Energy Producing Nutriment and Protein as Affected by Sodium Deficiency

Abstract

In a growth, metabolism, and body analysis experiment, by the paired feeding method, sodium deficiency unfavorably affected the appetite, the increase in weight, the storage of energy and the synthesis of fat and protein—the proportion of the energy stored as fat being the larger with a sodium supplemented than with a sodium deficient diet. There were no significant differences in the digestibility of the protein, or in the digestibility or the metabolizability of the energy producing nutrients, of the two diets, or in the moisture contents of the bodies of the two groups of rats. The heat loss was significantly higher with the rats on the sodium deficient than with those on the sodium supplemented diet. Decidedly more sodium was stored in the rat bodies from the sodium supplemented than from the sodium deficient diet, with resulting higher percentage of sodium in the bodies of the rats of the former group. With food intake restricted by their pair mates on a diet containing 0.007% sodium, rats on a diet containing 0.502% sodium increased in body weight from 51 gm. to 116 gm. during 70 days, that is, at a rate of 0.9 gm. per day, while a diet containing 0.007% sodium permitted growth at only about half the rate stated.