Meat
An increasing but still-small number of people in the U.S. have developed an allergy to red meat. Unlike other allergies, the cause of this newfound aversion seems to be transmissible—the result of a bite from the Lone Star tick. The allergy isn’t to red meat itself but a sugar found in the muscles of most mammals (but not humans) called alpha-gal. Somehow, the tick’s bite sensitizes a person’s immune system into overreacting to alpha-gal, the way it does in a person allergic to peanuts, for example. Unlike many “classic” food allergies (where an exposure to peanuts quickly leads to symptoms within minutes, for example), symptoms of a meat allergy can take hours post-exposure to show up.
