Alternative medicine can be a controversial subject. Some healthcare professionals love it, some are highly skeptical, and some people's opinions land somewhere in the middle. The interviewers are curious about where you stand on the issue and would like to see how you communicate in situations that may be a little uncomfortable.
Just like you would answer a sensitive question surrounding politics or religion, it's best to support both sides in some aspect when delivering your response. If you plan to voice a highly one-sided opinion, be prepared to give substantial evidence-based thoughts supporting your viewpoint.