Histamine is a chemical compound produced by special cells in your immune system, usually as a reaction to a perceived invader or irritant.

Histamine serves a useful purpose because it allows your body to expel potentially harmful substances, but it also helps your brain cells to communicate and triggers the release of stomach acid which is essential for good digestion. It’s only a problem if its levels become too high.

When excessive amounts of histamine are present you’ll experience allergic symptoms such as itchy skin, runny nose, and sneezing. These reactions are designed to expel the irritating substance as soon as possible. If you suffer with allergy symptoms, it’s important to consult a medical professional so any true allergic reactions can be identified and treated.

In histamine intolerance, there isn’t a true allergy present. Instead, histamine levels build up. Normally, histamine is quickly broken down after it’s done its job. This means the initial inflammatory reaction only lasts a short while. This process needs certain enzymes, so if you’re not very efficient at producing these enzymes, or they’re not functioning optimally, histamine levels may rise. ¹

Excess histamine in your body can also be due to excessive production, reduced breakdown, or diet related through eating certain foods. ² Such foods include alcohol, fermented foods like sauerkraut, processed and smoked meats, aged cheeses, dried fruit, avocado, aubergine, pineapple, shellfish and spinach, which are high in histamine. Other foods can trigger the release of histamine in the body. These include bananas, strawberries, certain nuts, tomatoes, citrus fruits, and some food additives. ³