ABSTRACT
Previous prefast preparations to eliminate the surplus sodium in order to study the true saluresis of fasting resorted to the use of Kempner rice diet. The pattern of the natriuresis of fasting could be changed by the use of a new method of prefast preparation in which cadbohydrate is eliminated and the surplus sodium is mopped up by the use of diuretics. This is taken as an evidence that carbohydrate exerts an effect on the saluresis of fastitog not only after fasting but also in the prefast period. By excluding the carbohydrate load inherent in the kempner prefast, naturesis was noticed to start on the first day instead of the second day, thereby bringing it down to the sphere of practical applicability in the management of obesity . By sparing this first day the one day a week fast assumes a practical value