Do they think that they are healthy because The Doctor told them? To quote what our mothers told us when we were kids: "If your friend told you to jump off a building, would you do that?" Well, given the absurdly dangerous drugs that The Doctor tells them to take, "jumping off a building" isn't so far-fetched. The basic problem here is that so many people have abrogated all thinking/ reasoning in the realm of "health care" to The Doctor. THINK! How can you call yourself healthy, living on dangerous chemicals on a daily basis, getting parts cut out, and losing functionality?
I look back to when my father was diagnosed with diabetes at the age of 40. The Doctor told him "Don't worry, Fred. Diabetes is the healthy man's disease." Really? Is that why my father died at 53? Is that why diabetes is one of the major killers? What my father's doctor said is downright stupid. My father's acceptance of that was, also, downright stupid. Yes, you as a lay person, a non-member of the medical priesthood, have the responsibility to think for yourselves. Parents! You have the responsibility to think for your children.
So, what is health? Dorland's Medical Dictionary defines health as "a state of optimal physical, mental and social well-being, and not merely the absence of disease or infirmity."