In simple terms, psychology is the study of the psyche (or the soul). In practical terms this means the study of human behavior including healthy mental functioning as well as mental illnesses. Mental health is the practical application of what psychologists have learned over the years. So psychology is the knowledge and mental health is the practical application of that knowledge.
A psychologist generally has a Ph.D. in psychology. She may focus on research or therapy and may do both in actual practice. Psychiatrists also study mental and emotional functioning. Psychiatrists have an M.D. and can prescribe medications, something psychologists and mental health workers cannot do.
When it comes to working in the field of mental health, there are certain degrees and licenses that bring with them particular privileges and responsibilities. Psychologists and psychiatrists can call themselves therapists. Those with a masters in counseling, social work, and other related fields can attain licenses that allow them to call themselves therapists. These include the Marriage and Family Therapist (MFT), formerly the Marriage, Family, & Child Counselor (MFCC), a Licensed Professional Counselor (LPC), and Licensed Clinical Social Worker (LCSW).
There are other specialties that are called therapy but do not have the same stringent requirements as those above. There are art therapists, music therapists, and sex therapists, to name a few. It should also be noted that the requirements for doing therapy are different from state to state. An MFT in California may have more stringent requirements than an MFT in North Carolina. North Carolina offers an LPC but California does not. These differences can be significant and not all states recognize licenses from other states.
Any ordained minister can do counseling and call him or herself a pastoral counselor or religious counselor. Anyone can call themselves a spiritual counselor with no degrees or licenses.
Within psychiatry there are specialties. A psychoanalyst is trained in a specific form of therapy, usually Freudian or Jungian. Not all psychiatrists are psychoanalysts. Not all psychiatrists, as with psychologists, work in the mental health field directly, do not do individual or group therapy.
Diversity Within Mental Health
Mental health is itself a very diverse field with many levels of professionals as well as those with lesser degrees or training. There are psychiatric nurses, a specialty within the nursing field. In any mental hospital or any hospital with a mental health ward there are many different jobs with differing requirements but all are active in mental health.
There are social workers who are case workers and may not be LCSWs. They cannot do therapy.
In private institutions like residential facilities for the mentally ill or other mental health facilities, unlicensed individuals may serve as counselors. Many unlicensed mental health workers, individuals without advanced degrees, play an important part in the mental health system.
To Recap: A psychologist can do research, teaching, and/or therapy. A psychiatrist can do therapy or research. Only a psychiatrist can prescribe medications because she is also an M.D. A number of different licenses, all requiring certain degrees, allow an individual to do therapy. All of these therapists can take insurance. Other types cannot. There are many types of counselors, some with degrees, but anyone can call themselves a counselor.
Anyone seeking therapy should investigate thoroughly before committing to an individual. Get references and check credentials. This is not to say that many counselors are not very good at what they do. It is just a cautionary note for when you decide to put your psyche into someone else’s hands.