Recently, I spent some time in psychotherapy to figure out where to go in my career. I wasn't prescribed any drugs or diagnosed with any problem. The short answer is yes. An insurance carrier is trying to assess risk when analyzing an applicant. Owning fast cars, living in crumbling buildings, and having a health history that may require further treatment are all considered to potentially pose greater risks than the one's carriers have considered when setting their basic insurance rates.
Carriers require full disclosure of all information.
They try to ask enough questions in order to assess the risks they take when they insure you. What may seem irrelevant to you may be quite relevant to a carrier. You should answer all questions asked on the application fully and truthfully. If you fail to disclose all medical information, even some informal psychotherapy visits, you risk having the carrier rescind your policy later on. It may not seem like a big deal to you, but it's fraud to them.