Do diamine oxidase (DAO) supplements for histamine intolerance really work?

Answer:

Histamine intolerance refers to a wide range of symptoms (such as itching, rash, migraine headache, gastrointestinal distress and difficulty breathing) that can be triggered by eating foods rich in histamine (fish, cheese, sausage, wine, and beer) or by taking certain drugs. There is evidence that, in some people, symptoms of histamine intolerance can be caused by low activity of the DAO enzyme, which helps to break down histamine in the body. Supplements containing DAO are promoted to help break down histamine to reduce symptoms.

Sign in to the full answer for details about what studies of DAO supplements have shown, dosage used, and which supplements promoted for breaking down or blocking the effects of histamine are similar to what has worked in clinical trials. Products covered include Histamine Block by Seeking Health, Histamine Blocker by Bravado Labs, Histamine Digest by Omne Diem, Histamine Manager by Healthy Habits Living, Naturdao, Hist-Resist by Vinco, HistaEze by Designs for Health, and Natural D-Hist by Ortho Molecular Products.