The term “mental illness” refers to a wide variety of diseases, which are disorders that affect mood, thinking and behavior. Examples of mental illness include depression, anxiety disorders, eating disorders and addictive behaviors.
Many people manifest mental health problems from time to time. But a mental health problem becomes a mental illness when the signs and symptoms become permanent, cause stress and affect the ability to function normally.

Mental illness can make you feel very bad and cause problems in daily life, for example, in school, work or interpersonal relationships. In most cases, the symptoms can be treated with a combination of medications and talk therapy (psychotherapy).