Did you suffer from an illness in your past which has gone but its affects still remain in you?
You say mostly your anxiety is health related, so is there a health issue? Or is this something different than your normal anxiety? The answer to your question is, yes, many including me have anxiety that is more there than not there. I've also had an anxiety problem where it was only there if I had to do something I had developed a phobia to, and I've had it where it was just occasionally. So it does differ by the person and at different times in life. If yours is getting to a point where it's getting harder to function, have you sought out therapy?