Margarine

Plain fat isn't typically a big histamine concern, but margarine is rarely just fat — and what's added is where the issue tends to come in.

• Additives and preservatives — commercial margarines often contain emulsifiers, flavor enhancers, and preservatives that may be problematic for people with histamine sensitivity, independent of the fat itself

• Compared to butter — plain unsalted butter is generally considered lower risk than margarine for histamine sensitivity, largely because it has fewer additives, though some people with dairy sensitivity may find butter its own challenge

Reading the ingredient list matters more here than the fat content itself.