Complementary health practitioners in the United States fall into two legal categories that look similar from the outside. One holds a state license; the other holds a private credential.
A license is a state grant of permission
Licensing means a state legislature has defined a scope of practice, created a board and made it unlawful to practice or use the title without meeting requirements.
Requirements typically include graduation from an accredited program, a national examination, continuing education and a background check, with the board holding disciplinary power.
The board is the practical difference. A complaint has somewhere to go, an investigation can happen, and the credential can be suspended or revoked.
Certification is a private arrangement
A certification is issued by an organization rather than a state. It attests that someone completed a curriculum and passed that body's assessment.
Standards vary enormously between certifying bodies, and nothing prevents a new body from forming with its own requirements and its own credential letters.
A certifying organization can withdraw its certificate, but it cannot stop anyone from practicing, because in an unlicensed field practice was never restricted to begin with.
Which fields are licensed varies by state
Chiropractors are licensed in every state. Acupuncturists are licensed in most. Massage therapists are licensed in a large majority, with different hour requirements in each.
Naturopathic doctors are licensed in some states and not others, which means the same training produces a regulated professional in one state and an unregulated practitioner across the border.
Yoga teachers, health coaches, energy practitioners and most breathwork instructors are not licensed anywhere, and their credentials come entirely from private schools and associations.
Scope of practice is written narrowly
Where licensure exists, the statute specifies what the practitioner may do. Scope typically excludes diagnosing disease, prescribing, ordering imaging and performing invasive procedures.
Some states permit licensed naturopaths to order laboratory tests or prescribe from a limited formulary, and the details differ enough that a general description is unreliable.
Practicing outside scope is the most common disciplinary issue, and it is often what separates a legitimate practitioner from one making claims about treating disease.
What a consumer can verify
In a licensed field, the state board maintains a searchable roster showing status and any public discipline. That record is the strongest verification available.
In an unlicensed field, the credential can only be checked against the issuing organization, which reveals what training was completed but says nothing about conduct.
Anyone with a diagnosed condition should keep their physician informed about complementary care they receive, since a practitioner outside the medical record cannot coordinate with treatment.