主要是食品添加剂gluten过敏

杂交小麦&食品添加剂("consumption of a food additive termed
“vital gluten,” which has tripled since 1977. Vital gluten is a food
additive made from wheat flour, and it is added to various food products to
improve their characteristics, such as texture.)的推广直接导致gluten在面粉中
的含量增加了，所以现在很多人对gluten过敏，而以前就很少。还有牛奶，也跟50年代
的牛奶大不相同。