Mental Health Disorder is an illness that is diagnosable. The illness affects a person’s thinking, emotional state and behavior and disrupts their lives. Examples are depression and anxiety which is common and the not so common schizophrenia and bipolar disorder which can lead to a disability.
Mental Health Problem is a much broader term that included both mental health disorders and symptoms of mental disorders that may not be severe enough to warrant a diagnosis of a mental disorder.
Slang terms used for mental health issues are crazy, psycho, mad, loony, nuts, cracked up and wacko. None of these terms are helpful for give much information on the subject.
Helpful Resources for your mental health and if you are assisting others.
National Institute of Mental Health – http://www.nimh.nih.gov
World Health Organization – http://www.who.int/topics/global_burden_of_disease/en/
From: Chapter 1 of Mental Health First Aid USA ISBN:978-00692-60748-0