Dr. Anna Reid is appearing before the Commons justice committee which is studying legislation that would bring combat sports, including mixed martial arts, under supervision and regulation.
The bill would update the 80-year-old Criminal Code section dealing with prize fights.
Combat sports are currently in a sort of legal limbo in that they technically may be illegal under the law, but are condoned.
Supporters of the bill say it will promote safer practices in mixed martial arts, a popular — if often bloody — contest.
Reid says this kind of combat fighting is dangerous and often produces serious head injuries.
The association's general council voted in 2010 for a ban on mixed martial arts prize fighting matches.
The present legislation passed the Senate with broad support and a similar bill had strong support on the Commons before it died due to prorogation.
Reid says the doctors don't oppose combat sports such as judo and karate.
"However, cage fighting, like boxing, is distinct from many other sports, in that the basic intent of the fighter is to cause harm in order to incapacitate his or her opponent," she said.
"And an activity in which the overriding goal is to pummel one’s opponent into submission does not promote good health."
She said there is little evidence about the long-term risks from this kind of fighting, but noted studies show boxing poses risks of head trauma and subsequent neurological problems.
"For parliamentarians, and for society, the question of whether to legalize MMA under the Criminal Code therefore comes down to a choice: a choice between money and health."
She said it is her duty to protect the health of patients and to promote non-harmful activities and it is the mandate of the CMA to advocate for the highest standards of health and health care.
"For me, as a physician, it is about putting health first. I cannot condone punches to the head."