There are many serious complications of anorexia, including fainting from low blood pressure, electrolyte disorders, being intolerant to cold, constipation, decreased energy, changes in mood, anemia, kidney failure, osteoporosis (brittle bones), suicide, heart rhythm abnormalities, heart failure, sleep problems, confusion, irritability, and dizziness and even death.

Some physical signs that are found in patients with bulimia include an enlargement of the parotid glands (causing chubby cheeks), dental erosions (especially on the back surfaces), and having calluses on their knuckles. Other signs found in teens with eating disorders include having dry and brittle hair, losing hair, and having muscle wasting.