Effect of mild infectious illness on nitrogen metabolism in patients on a modified fast.

To assess the catabolic effects of mild infectious illness on protein metabolism, the metabolic responses to incidental infections were studied in four obese patients undergoing a modified fast consisting of a low calorie diet essentially free of carbohydrate but meeting protein needs. In six infectious episodes investigated, there was no change in urinary nitrogen excretion. Nitrogen balance was positive when protein intake was maintained at 0.8-1 g/kg body weight in four of five episodes, despite intakes of less than 700 kcal. These preliminary data from patients experiencing infections under these conditions suggest possibilities for significant reduction in catabolic losses in other stress situations.