In planning nutritional rehabilitation of a patient with protein deficiency, certain findings in studies of protein repletion in animals appear pertinent. It has been shown that the utilization rate for a particular essential amino acid for repletion exceeds the rate for maintenance by a factor of 2 to 5. On this basis, the protein needs of depleted patients would be at least double those of normal subjects (17). The severity of protein depletion can be estimated only grossly with present techniques. The following data, considered together, should prove helpful: the amount of weight lost (actually the loss of muscle and other active metabolizing tissue), the extent of the decrease in total circulating plasma protein, particularly albumin, and in tissue proteins as reflected by this decrease and the daily loss of protein or nitrogen in urine, stools, exudates and effusions. It should be remembered also that “amino acid requirements for repletion of specific tissue proteins vary according to the structure of the protein and the position it holds in the dynamic state of the body” .