There are many occasions when physicians or surgeons wish to use a diet with the least possible residue, particularly in the treatment of patients with diarrhea and following operations about the rectum or anus. If the fecal residues can be made small enough, and if defecation can be postponed for a week or more, not only will the patient be spared much distress, but healing wounds can be kept clean. Considering the importance of this problem, it is surprising to find practically no mention of it in most of the well known textbooks on dietetics. According to Prausnitz,1 Bischoff and Voit,2 Müller,3 and Rubner,4 so long as the foods given are completely utilized, the amount of feces voided will remain about the same with different diets. As is well known, a considerable portion of the fecal material is made up of dead bacteria and intestinal secretions; so, even during starvation,