Doctors have advanced medical knowledge, and advanced medical equipment that could diagnose diseases much better than an individual person without medical training.
However, there are times when a person DOES know his/her body, in basic terms, better than a doctor.
Even doctors acknowledge this. Even doctors acknowledge that they are not infallible.
I'm not exactly a connoisseur of folks remedies; I take Tylenol or Advil for pain. However, there are certain herbs which do have medicinal qualities. As for witchcraft, homeopathy, etc., I don't believe in that crap.