Bulimia is an eating disorder, but it can also be referred to as a mental disorder. According to the National Association of Anorexia Nervosa and Associated Disorders (ANAD), eating disorders such as bulimia are the most fatal mental conditions in the United States. This fact is attributed to long-term health problems, as well as suicide. Some patients with bulimia also have depression. Bulimia can cause people to feel shame and guilt about their inability to control compulsive behaviors. This can worsen preexisting depression.