Serum transthyretin is an ideal marker for monitoring patients who are malnourished or have metabolic consequences of acute stress injury because it has a short half-life, it measures the level of metabolic deficit, the response to nutritional metabolic support, and because it is a prognostic indicator. Mounting clinical evidence indicates that the use of transthyretin to assess and monitor a patient's nutritional status results in improved treatment outcomes and lower overall healthcare costs.