Histamine is a chemical found in some of the bodys cells that causes many of the symptoms of allergies, such as a runny nose or sneezing. When a person is allergic to a particular substance, such as a food or dust, the immune system mistakenly believes that this usually harmless substance is actually harmful to the body. In an attempt to protect the body, the immune system starts a chain reaction that prompts some of the bodys cells to release histamine and other chemicals into the bloodstream. The histamine then acts on a persons eyes, nose, throat, lungs, skin, or gastrointestinal tract, causing allergy symptoms.
Histamine intolerance, sometimes called histaminosis, is an over-accumulation of dietary histamine in the human body. It occurs when the activity of the enzyme diamine oxidase (DAO), which metabolizes histamine, is limited, and histamine taken up by the diet and formed in the body is only partially metabolized. The consumption of histamine-containing food (e.g., red wine or hard cheese) leads to a pseudoallergic reaction. Symptoms of histamine intolerance include headaches, nasal congestion, fatigue, itchy skin, hives, and irregular menstrual cycles. In more severe cases, it can cause abdominal cramping, tissue swelling, high blood pressure, irregular heart rate, anxiety, difficulty regulating body temperature, and dizziness. Foods high in histamine, such as fermented foods and dairy products, dried fruits, avocados, spinach, processed or smoked meats, fish and shellfish, and aged cheese, can trigger inflammatory reactions and other negative symptoms.
