Dear Lucy: A few years ago, I noticed that my armpits would itch every time I ate an apple. This symptom would go away after a few minutes, and I continued to eat apples, because I figured that what doesn't kill you might desensitize you—at least within reason. I eventually started eating apples every day, and now I often eat two apples a day without any itching at all. Did I "cure" an allergy to apples by exposing myself to them, or was I never allergic in the first place? —Johnny Appleseed
