Why do you think illness anxiety disorder (hypochondriasis) continues in a person?
What perpetuates his/her obsession with health and illness?

I think it continues in a person because of the surrounding environment they are in. Our health is the most important priority and dictates whether we live or die essentially which then causes more anxiety in a person. The importance of health in a person can cause continuous anxiety because it is always going to be a large part of our lives. Their obsession perpetuates from constant reminders that their health dictates their pain and ultimate survival.

Hope this helped! This is merely an opinion :)

having the certification could make the person more required to do a certain thing then another.this could also lead to different job offers or opportunities.

answer: no, they are not.*

although rubber bands that contain excessive amounts of dye, toxins, or additives are sometimes toxic, most rubber bands do not cause any health issues. since they are typically made of latex, (a natural substance that is extracted from trees) they are not dangerous in any way if you chew them or accidentally ingest a piece of rubber band. however, chewing rubber bands does pose a choking hazard and is not a good habit to have.

*depending on the type of rubber band. the typical rubber bands that you see at stores are not toxic, but other types of rubber or latex that contains certain chemicals may be unhealthy and hazardous.