Anorexia

Cancer-related anorexia is very different from the publicized eating disorder of similar name. Cancer-related anorexia is an involuntary loss of appetite or loss of desire to eat that occurs because cancer alters the body's appetite signals and metabolism. This occurs in almost half of all patients with cancer.

What causes anorexia when cancer is present?

Cancer cells don't create and use energy the same way that normal cells do. Cancer cells use much more effort and resources to create energy-but they only produce 5% of the energy of a healthy cell. Because cancer cells waste energy, the body becomes tired and undernourished. To make up for this energy shortage, cancer cells "steal" energy from normal cells, which starves those cells. In addition to this energy shortage, cancer radically changes the way the body breaks down and uses proteins, lipids, and glucose. The body doesn't need more food-instead, it needs certain amino acids, hormones, and other compounds, all of which can be delivered orally or via injection.

Consequences of anorexia

Anorexia can decrease your response to cancer treatments or increase the side effects you feel after treatments-so talk to your oncology nurse or other healthcare provider about it. Anorexia also decreases your quality of life. Untreated anorexia can develop into something more serious called cachexia, a debilitating state of involuntary weight loss and muscle wasting.