What should I know about was ist histamin?

Histamine is a biogenic amine that acts as a signaling molecule in the body, involved in immune responses, stomach acid secretion, and sleep-wake regulation. It occurs naturally in foods such as aged cheese, wine, sauerkraut, and fish. Histamine intolerance arises when the enzyme diamine oxidase (DAO) fails to break down histamine adequately, leading to symptoms like headaches, flushing, diarrhea, or palpitations. Diagnosis is clinical and often involves dietary changes and possibly DAO supplementation. MyBody-X currently does not offer specific genetic tests for histamine intolerance, although variants in DAO genes (e.g., rs10156191) are known. However, the evidence for such tests is limited and not sufficient for reliable diagnosis. If histamine intolerance is suspected, a doctor should be consulted. The provided knowledge contexts contain no information on histamine, so this answer is based on general medical knowledge.