American Journal of Clinical Nutrition, Vol 19, 227-231, Copyright © 1966 by The American Society for Clinical Nutrition, Inc.

Dietary Nitrogen Utilization in Young Men Fed a Diet in Solid and Liquid Form

¹ From the Department of Nutrition and Food Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

Six young adult male subjects participated in an experiment designed to determine the effect of diet consistency per se on nitrogen utilization. A diet of conventional foods supplying 1 gm. protein per kg. was fed in solid form for six day adaptation and experimental periods. During the next six day period the same diet was homogenized with water to the consistency of a thick milk shake. For the final six day period the solid diet was again provided. Total water, protein and caloric intake remained constant during the entire experimental period. Urinary nitrogen, creatinine, total urinary volume and specific gravity were measured daily during the periods of liquid and solid diets. Fecal nitrogen excretion was determined on three day pooled samples. There was no measurable effect of the consistency of the diet on the utilization of dietary nitrogen. Psychologic tests made on the subjects during the experimental periods did not detect changes due to consistency of the diet. The results support the use of liquid diets in nitrogen balance experiments in man.