Relationship between preoperative nitrogen balance and energy and protein intake in patients with esophageal cancer.

This article focuses on determining the energy and protein intake levels required to maintain positive nitrogen balance (NB), an indicator of protein utilization, in preoperative esophageal cancer patients. The study of 79 patients found that all individuals consuming at least 30 kcal/kg/day of energy and 1.3 g/kg/day of protein exhibited positive NB, while lower protein intake was associated with a higher rate of negative NB. Additionally, urinary urea nitrogen (UUN) excretion, a marker of protein catabolism, was positively associated with retinol-binding protein (RBP) and skeletal muscle mass index (SMI), suggesting better short-term nutritional status correlates with increased protein turnover. These findings support nutritional guidelines recommending higher protein intake for this patient group to maintain anabolic balance before surgery.