No, green beans are not high in histamine. However, green beans (also known as string beans) are both moderate in lectins and thought to be a so-called “histamine liberator.” This is a term used to refer to foods believed to cause histamine release in the body, despite not containing high levels themselves. Thus, green beans should be avoided in the first month or so of an elimination diet, until it can be determined that they don’t trigger a reaction in you.
Even once you reintroduce green beans, make sure to avoid canned green beans, as they will have higher levels of histamine due to the canning & preserving process. Other foods commonly classified as “histamine liberators” include: tomatoes, grapes, peanut butter, and oranges.