Hypermetabolism is the physiological state of increase rate of metabolic activity. The impact of the hypermetabolic state on patient nutritional requirements is often understated or overlooked. Hypermetabolism typically occurs after significant insult to the body. In hospitals and institutions, the most common causes are infections, sepsis, burns, multiple trauma, fever, long-bone fractures, hyperthyroidism, prolonged steroid therapy, surgery and bone marrow transplants.