Not too different from lactose intolerance, which you’re probably familiar with. Some people don’t produce the lactase enzyme to break down lactose, the protein found in milk. Likewise, some people don’t have enough of the enzyme DAO to break down histamine.
People with Histamine Intolerance develop symptoms between 2 and 24 hours after exposure to foods rich in histamine.
Diseases like colitis, crohn’s, celiac, and lactose intolerance can also damage the intestines enough to reduce the activity of DAO. When this happens, we call it secondary Histamine Intolerance.
Symptoms are diverse and confusing.
