Water Intake and the Blood Sugar Level

Abstract

In our studies which have involved blood sugar determinations on rats, considerable effort has been expended to secure uniformity both in the animal material and in the routine care of the colony. But in spite of all this care to secure uniformity we have found at times that the normal blood sugar level showed considerable variation. 1 Recently, upon our return from the summer vacation, the routine normal control series of sugar determinations was made. At the same time, determinations were made upon a group of rats used in the study of prolonged high carbohydrate feeding. 2 These animals represented the 4th, 5th and 6th generations which had been kept continuously on the high carbohydrate diet. It was noticed that the sugar levels in both groups were not only high but far above any mean value thus far obtained. Two and a half months previously the water supply had been changed from the open jar to the tubulated-bottle system. It had been observed that some of the water bottles did not deliver properly. The question arose, therefore, as to whether a possible water deficiency due to difficult access to the water by the tubulated-bottle method was associated with the high sugar level. The purpose of the observations to be reported was to determine the influence, if any, of the water consumption by the open jar and the tubulated bottle upon the blood sugar level.

After the initial observations were made, the entire colony was supplied with open water jars and the blood sugar levels were determined one week later and at subsequent intervals for 8 weeks. Approximately 50 observations were made on each point on the curve for the normal controls.