Anchovies are particularly important for people with eczema to know about because they hide in many foods where fish would not be expected. Caesar dressing, Worcestershire sauce, some pizza toppings, Asian fish sauces (nam pla, nước mắm), tapenade, and some bouillon cubes all contain anchovy. This means someone who thinks they are avoiding fish could be consuming anchovy-derived products daily without realising it.

Anchovies carry a double histamine risk: their muscle naturally contains high levels of the amino acid that bacteria convert to histamine, and they are traditionally preserved by salt-curing and fermentation — a process that further increases histamine content. The combination makes anchovies one of the higher-histamine fish products available.