nettle

According to the SIGHI classification, stinging nettles are considered a problematic food. This is because the stinging hairs of fresh stinging nettles naturally contain high levels of free histamine, acetylcholine, and serotonin. Although heat treatment or drying destroys these stinging mechanisms, in sensitive individuals with histamine intolerance, consuming stinging nettles (e.g., in the form of teas or spring spinach) can trigger a pseudoallergic reaction. On the other hand, some studies suggest that nettle extract may, paradoxically, act as an antihistamine and mast cell stabilizer; however, as part of a low-histamine diet, extra caution is necessary due to the natural content of biogenic amines in the fresh plant.