Like tomatos, basicly everything what got the color red
;), sauerkraut, chocolate, beer, wine
, cheese and so on. As soon as you eat sth histamine rich your body reacts with a allergic reaction. To diagnose HI it needs an common blood test, nohting special ;). To our time there are dietary supplements already available which can help you to handle it. For example I'm using Daosin, it makes it possible to eat everything, even if histamine rich or not.