What Is Mental Illness?

Mental illness is nothing to be ashamed of. It is a medical problem, just like heart disease or diabetes. According to the American Psychiatric Association, mental illnesses are health conditions involving changes in emotion, thinking or behavior (or a combination of these). Mental illnesses are associated with distress and/or problems functioning in social, work or family activities.

  • Mental illness is common. In a given year:
  • Nearly one in five (19 percent) U.S. adults experience some form of mental illness
  • One in 24 (4.1 percent) has a serious mental illness
  • One in 12 (8.5 percent) has a diagnosable substance use disorder

Mental illness is treatable. The vast majority of individuals with mental illness continue to function in their daily lives.

Mental illness does not discriminate; it can affect anyone regardless of your age, gender, geography, income, social status, race/ethnicity, religion/spirituality, sexual orientation, background or other aspect of cultural identity. And it can take many forms. Some are mild and only interfere in limited ways with daily life, such as certain phobias (abnormal fears). Other mental health conditions are so severe that a person may need care in a hospital.