Critically injured patients are characterized by hypermetabolism and accelerated catabolism, leading to rapid malnutrition. The prevalence of malnutrition among hospitalized patients is as high as 50% [1,2]. Inadequate nutrition is associated with an increased risk of morbidity, mortality, and longer hospital stays [3]. Most trauma patients are well nourished before injury. These patients are candidates for nutritional support because of the hypercatabolic state associated with multiple trauma. Adjuvant nutritional therapy has developed an expanding role in clinical intensive care, as the medical community begins to understand the immune system, sepsis, multiple organ dysfunction, and wound healing. With a better understanding of the endogenous responses to injury, more can be learned about the mediators of these responses. These mediators can be manipulated through improved insight into nutritional support, its timing, complications, and its role in the full recuperation of patients from the acute phase to rehabilitation.