An increase in appetite can be a normal physiological response that occurs, for example, in children and adolescents during periods of growth or following strenuous activity or excessive caloric demand. In some cases, an increase in appetite can be a sign of an abnormal condition, such as some endocrinologic conditions, including diabetes, hyperthyroidism, and Graves' disease. Increased appetite may also be seen in certain emotional or psychiatric conditions, as well as a response to stress, anxiety, or depression. Episodes of hypoglycemia can cause excessive hunger as well. Certain prescription drugs can also increase appetite. It is important to take into account the context and any related emotional or physical factors when determining whether one has an abnormally increased appetite. Polyphagia is the medical term for excessive eating.

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