Russell Skinner, MD
Understanding histamine could be the answer to your migraines. There is a lot of confusion about histamine and how it can either cause or prevent migraines. Here’s a guide to help you figure out how to control histamine and thus reduce occurrence of migraines.
A Two-Edged Sword
Histamine is an amine (a chemical which is made from an amino acid) that is involved in tasks within the immune and neuroendocrine systems, neurotransmission, gastric secretion, cell life and death, and development. It is part of a local immune response to cause inflammation. It performs several important functions in the bowel and acts as a neurotransmitter or chemical messenger that carries signals from one nerve to another. It is able to affect the immune, digestive and nervous systems by affecting cells in many different parts of the body.
Histamine has a particularly central role in allergic reactions. It causes vasodilation (the expansion of blood vessels) as well as makes capillaries leaky (increased permeability). This causes the characteristic swelling and inflammation associated with allergic reactions. In addition, histamine causes the airways to shrink, which can make breathing difficult.
Histamine plays a major role in the production of stomach acid. It also plays an important role in a part of the brain known as the hypothalamus. According to a 2001 article in Progress in Neurobiology, histamine is crucial in modulating anxiety, the release of stress hormones, and arousal.
One lesser known fact about histamine is that it is released by the body to trigger thirst. When you are dehydrated, your histamine levels are elevated, resulting in suppressed white blood cell production, the very things that help you eliminate allergy responses. So, next time you experience symptoms of allergies, ask yourself if you have been hydrating correctly.
The Link Between Migraines and Histamine
Migraine is defined as a “disorder in which periodic episodes of headache are associated with spells of hypersensitivity of the senses (bright lights, sounds) causing nausea and vomiting”. These headaches are often accompanied by a “migraine aura“, an altered perceptions of reality, such as vertigo, shining lights or temporary blind spots. It might also come with distorted sense of taste and smell, symptoms of paralysis, difficulty in speaking or hearing sounds.
As far as we know, histamine seems to be one of the factors most closely linked to the ailment of migraines.
An Enzyme Called DAO
Under normal conditions, excess histamine is broken down by specific enzymes, especially diamine oxidase (DAO). The products of histamine breakdown are then excreted via the kidneys in urine. Usually this will ensure that histamine levels do not exceed a person’s “limit of tolerance” (the level above which symptoms develop). However, when the amount of DAO is insufficient, histamine levels rise and typical histamine intolerance symptoms develop. Please see this article.
In a recent study, the prevalence of DAO deficiency in patients with a confirmed migraine diagnosis was measured and it was determined that 87% of the migraine patients had an enzyme deficiency.
It's important to note the following:
If you suffer from migraines because of an overabundance of histamine in your body, you may reduce your episodes by:
The amount of histamine entering the body from dietary sources can be significantly reduced by following a histamine-restricted diet. A low-histamine diet, plus supplemental DAO should reduce the amount of exogenous histamine entering the body to almost nil. It is very important to understand that this approach will not reduce the amount of histamine produced within the body. The effects of this histamine must be addressed by other methods of control such as antihistamines, mast cells stabilizers, and other appropriate therapies depending on the source of the endogenous histamine.