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Histamine Intolerance

Biochemistry of Histamine Intolerance

By July 18, 2021January 23rd, 2024No Comments
histamine intolerance

Histamine Biochemistry and DAO

Look at the histamine biochemical pathways and you’ll see why the enzyme supplement DAO (diamine-oxidase) helps many people with their symptoms of histamine intolerance (HIT)!

The image shows the biochemistry of how histamine gets degraded in the body. The breakdown of histamine is through two pathways:

  1. via the enzyme DAO in the gut, or
  2. via the enzyme HNMT in the rest of the body.

Some people just don’t make enough of their own DAO enzyme.

There could be many reasons for it, such as:

  • Genetics resulting in producing less DAO
  • High requirements for DAO due to a diet high in histamines or foods (or medications) that trigger histamine release
  • Excessive release of histamines in the body due to an immune response
  • Intake of substances that block DAO such as alcohol
  • Decreased production of DAO due to poor gut health or aging

If there is a deficiency of DAO in relationship to the amount of histamines that need to be cleared, taking a DAO supplement (Histamine Digest) can support the clearing of histamines from foods, or from foods (and medicines) that trigger the release of histamines.

(The DAO pathway also requires nutritional cofactors – iron, B12, B6, copper and Vitamin C.)