DAO

What Is DAO?

DAO is short for diamine oxidase, an enzyme the body makes on its own. It is produced by the cells lining the small intestine. This supplement supplies the same enzyme from pig kidney, a tissue rich in it, in a tablet coated to hold together in stomach acid.

How It Works in the Body

Histamine is ordinary biology. The body makes its own and uses it as a signal. It also turns up in food, because bacteria produce it as protein breaks down in aging and fermenting.

Diamine oxidase is a copper enzyme with an unusual active site: a quinone formed from one of its own tyrosine residues, sitting next to a copper ion. It takes the amine group off histamine and leaves an aldehyde, ammonia and hydrogen peroxide. That reaction is the body's main route for handling histamine that comes in with food. It happens in the gut, not in the blood.

What It Supports

• Histamine from food: Diamine oxidase supports the body's normal handling of histamine that arrives in food.
• A copper enzyme: Diamine oxidase carries a copper ion and a quinone built from its own tyrosine.
• Where it acts: The enzyme stays in the digestive tract and works on what passes through it.
• A coated tablet: The coating stays closed in stomach acid, so the protein reaches the small intestine.

Who It May Suit

Adults whose meals lean on aged and fermented foods. The appeal here is an enzyme that acts in the gut, not a nutrient. It comes from pig kidney, so it does not suit vegetarian, vegan, kosher or halal eating.

Good To Know

Enzymes are measured by activity, not by weight, which is why this one carries a unit count beside the milligrams. Talk with your healthcare provider before use, especially if you are pregnant or nursing, or if you avoid pork. Raise ongoing digestive complaints with a clinician too, rather than working around them.