“…These quantities of nitrogen and calories, and those used in other postoperative studies where nitrogen equilibrium was not achieved (Abbott et al, 1957;Larsen and Breckner, 1965;Johnston, Marino and Stevens, 1966;Hallberg et al, 1967), exceed the theoretical requirements of patients recovering from operation. In our study the range of non-protein calorie intake varied from 6 kcal.kg-1 .day" 1 to 51 kcal.kg-1 .day" 1 and yet significant group differences only became apparent from the 2nd day after operation, after which there was a linear relationship between the improvement in nitrogen balance and the increase in calorie intake.…”