More than six dozen B.C. naturopaths are being investigated as their professional college continues to crack down on advertising violations.

By Tuesday, 73 B.C. naturopaths were under investigation, according to the College of Naturopathic Physicians. That's about 12 per cent of the practising registered naturopaths in the province.

"The majority of B.C.'s registered naturopathic doctors have taken the initiative to make sure their websites, social media channels and other advertising activities are in line with the rules," college registrar Phillipa Stanaway said in a news release.

The investigations are part of an ongoing enforcement sweep that started last year. The college gave naturopaths until Jan. 21 to make sure their websites, social media and other advertising were in line with the rules or face potential discipline and minimum fines of $500.

The majority of the investigations to date are about what the college describes as minor violations of its rules, including the advertising policy, according to Stanaway. Some naturopaths are under investigation for multiple infractions.

Forty-five of the investigations concern unverifiable claims about treatments or the use of patient testimonials, which are not allowed in naturopaths' advertising. Forty-two are about improper descriptions of professional status, including claims of specialization.

Three are related to the college's immunization standard, which says naturopaths can't spread anti-vaccination content, and can only advise patients against immunization if there is a documented medical reason.

"The college is pro-vaccination, holding the view that, for most patients and for the community, the benefits of vaccination vastly outweigh its risks," Stanaway said.

B.C. provincial health officer Dr. Bonnie Henry and CBC reporter Bethany Lindsay address five misconceptions about the vaccine for measles, mumps and rubella. 2:49

Any of the naturopaths currently under investigation could face sanctions for violations of college policies. The college says it's wrapped up 17 investigations so far, and asked for the people involved to sign consent orders that might include fines and undertakings to not repeat the violations.

The enforcement sweep began last May after CBC reporting showed that three B.C. naturopaths were advertising a homeopathic treatment for autism that falsely promised "complete elimination of autism spectrum expression."

The college immediately banned the practice, known as CEASE therapy and announced a crackdown on marketing materials.

There are 593 practising registered naturopaths in B.C. Another 61 registrants are non-practising.

Licensed naturopathic doctors are alternative medical practitioners who attend four-year graduate-level schools, where they study topics including herbal medicine, nutrition, body work and homeopathy. In B.C., they have the authority to prescribe drugs, and they can be certified to administer vaccines.