Polyphagia, also called hyperphagia, is the medical term for a feeling of extreme, insatiable hunger. It’s a symptom of certain health conditions. Eating typically doesn’t make polyphagia go away, except in the case of low blood sugar (hypoglycemia). Excess eating as a result of this feeling may or may not lead to weight gain depending on the underlying cause. In some cases, it’s associated with unexplained weight loss. An increase in hunger is a normal bodily response to situations like fasting or strenuous exercise. But intense, insatiable hunger like polyphagia is often a sign of a health condition that needs medical treatment, such as diabetes.