Complementary and alternative medicine
Alternative medicine is a catch-all phrase used in a variety of ways that can encompass a broad variety of concerns. It might be used, on the one hand, for any set of health, medical or therapeutic practices not blessed by the medical establishment and thus not covered by medical insurance. It might also refer, used by a different person, to practices believed by the established medical authority to be dangerous, deceptive or ineffective. It might even refer to matters on which the established medical authority has no opinion, either because no studies have been done or no opinion sought. Public debates include extreme viewpoints in conflicting directions, from on the one hand, banning anything and everything not blessed by the establishment, and on the other hand, to providing individual freedom to try a wide variety of therapies as long as they are not actually banned as dangerous or illegal and as long as no patently unprovable claims of efficacy are being made to potential clients.
This begs the question: who gets to decide? In the United State, the American Medical Association is the entity that is legally empowered to endorse or ban medical practices, and at least in theory, medical insurance is expected to cover therapies and approaches endorsed by the AMA. The U. S. Food and Drug Administration is supposed to prevent companies or individuals from marketing drugs or food which are not known to be safe, and also to prevent anyone from making claims of efficacy which are not supported by independent studies using accepted scientific methodology.
But many state agencies also become involved in regulating what is allowed or not allowed. For example, while medical insurance may not recommend or pay for therapeutic massage, chiropractic manipulation, or acupuncture (just for example), many states require practitioners of these arts to be licensed by a state agency intended to guarantee a certain minimum level of competence and training.
The history of such struggles and disputes is better told in articles related to a specific unofficial health approach. See the following articles about specific topics within alternative medicine: Chiropractic, Acupuncture, therapeutic massage, etc.