Malnutrition and metabolic abnormalities in cancer patients.

Malnutrition is a common problem in cancer patients. The most clear-cut cause is anorexia and a decrease in food intake. Other causes include alterations in carbohydrate, fat and protein metabolism which result in losses of energy and amino acids from the host. Understanding the pathophysiology of these changes will provide avenues to better nourish cancer patients and improve their quality of life.