Why does histamine cause headaches?
By now you’re likely quite familiar with what histamine intolerance is and the symptoms it may cause.
After reading about the symptoms of histamine intolerance, you can probably understand why you get hives and skin rashes as a result of histamines being released into the skin.
But... why would histamine intolerance be associated with such severe brain splitting headaches?
Especially since the brain itself does not contain pain receptors, and is unable to feel pain? The answer might surprise you…
Vascular headaches and histamine intolerance
While the brain doesn’t have pain receptors itself, the protective layers of tissue that surround the brain sure do.
When we look at the mechanisms of headaches, they typically occur as a result of an increase in blood flow to the blood vessels located around and within these tissues, which cause pressure that activates the pain receptors they contain.
These headaches, because of the effect on the vasculature, or blood vessels, are called vascular headaches.
So, what does this have to do with histamine intolerance?
Think about what you already know about what happens to the skin when you have a histamine reaction: it becomes red and swollen, in addition to the itching.
The reason for the swelling is an increase in fluid being deposited as a result of the heightened histamine load. And, now you know that an increase in fluid causes vascular headaches, so put the two together and you’ll quickly realise that an increase in histamine within the brain and its surrounding tissues can increase the pressure, which causes the pain (1).
Histamine compounds commonly deposit in these brain tissues as they are rich in the histamine H3 and H4 receptors. The rich histamine receptor distribution in the brain means that histamines form an essential part of neurological health, but it’s the excess that causes all of the problems (2).
The headaches are usually associated with pain in one location or multiple sites across the head, and it all depends on the receptors that are being activated.
When you have a headache along with tearing of the eyes, nasal congestion and/or runny nose, facial sweating and/or a sense of agitation, it’s usually a histamine-related headache.
Now that you know why histamine excess causes headaches and how you can distinguish between another type of headache, the next question is: what do you do to stop these terrible headaches (and other symptoms associated with them)?
Improve headaches by reducing histamine load
Reducing the amount of histamine that the body contains is the very first step to improving histamine-related headaches.
As you already know, one of the easiest ways to do so with relatively easy implementation is to follow a low histamine diet. Reducing the amount of histamine in your food, reducing the amount of histamine your body releases as a result of food, and reducing the impact on diamine oxidase (DAO) production all comes with eating a low histamine diet.
This brings me to the second step: increasing histamine breakdown with DAO.
DAO, as you know, is diamine oxidase, which is the primary enzyme your body uses to break histamine down. Research shows that many people who experience migraines are actually deficient in this enzyme (3).
In fact, around 90% of people who experience severe and debilitating migraines were found to have a deficiency in the ability to produce and maintain adequate levels of DAO (4).
Along with an increase in histamines in food, and/or an increase in the production/release of histamines by the body, there is an overload of histamines in the body, they flood to the brain and cause those terrible headaches we’ve been talking about. Taking supplemental DAO, which has been used in some European countries as an innovative approach to migraine treatment, is in its early stages of regulation, but the results are promising (4).
If you, like so many others with histamine intolerance, simply can’t get rid of those bothersome headaches, put your focus on your diet as a start, as each meal provides an opportunity to improve your health and symptoms. Here is a handy low histamine food list that can help to get you started.
Remember that histamine intolerance is not a primary condition, meaning that it does not simply occur on its own. While you’re trying to manage your symptoms, keep looking for the underlying cause of your histamine intolerance. You can read more in this article about all things histamine intolerance.
- Worm, J., Falkenberg, K. & Olesen, J. Histamine and migraine revisited: mechanisms and possible drug targets. J Headache Pain 20, 30 (2019).
- Alstadhaug, K.B. (2014), Histamine in Migraine and Brain. Headache: The Journal of Head and Face Pain, 54: 246-259.
- Izquierdo-Casas J, Comas-Basté O, Latorre-Moratalla ML, Lorente-Gascón M, Duelo A, Vidal-Carou MC, Soler-Singla L. Low serum diamine oxidase (DAO) activity levels in patients with migraine. J Physiol Biochem. 2018 Feb;74(1):93-99.
- Izquierdo-Casas J, Comas-Basté O, Latorre-Moratalla ML, Lorente-Gascón M, Duelo A, Soler-Singla L, Vidal-Carou MC. Diamine oxidase (DAO) supplement reduces headache in episodic migraine patients with DAO deficiency: A randomized double-blind trial. Clin Nutr. 2019 Feb;38(1):152-158.