What is Histamine Intolerance and what can you do about it?


Histamine is an inflammatory mediator. When a release of histamine is triggered, it helps the immune system respond to threats (e.g. infections, allergies (which are essentially the body’s “imagined” threats)). Capillaries are dilated to increase circulation and become more permeable to help white blood cells get to where they are needed. This is helpful when it’s needed and assuming the process is well-managed within the body.
As with many things in the body (cholesterol, estrogen, fibrinogen, cortisol), too much of a good, normal, natural thing can become debilitating or even life-threatening. Histamine intolerance is about the body becoming overloaded, where the amount of histamine present outweighs our ability to break it down or, detoxify.

Histamine comes from many sources. Externally, we primarily get it from our foods. Internally, we produce it in response to immune threats, and some of the microbes in our gut also produce it as part of their normal metabolism. In a healthy, balanced body, an enzyme in the GI tract (DAO, diamine oxidase) handles the histamine in our food. Internal to the body, another enzyme system handles intracellular histamine (histamine N-methyltransferase or HNMT). Of course, nutrition is key here too. Both enzyme systems require B vitamins and minerals as cofactors. And methylation (that pesky SNP issue again!) is also required to reduce intracellular histamine.

Unfortunately, there is no single lab work marker or panel that can readily identify histamine intolerance. Single, one-time measurements of histamine in the blood may be elevated due to specific triggers, but that doesn’t mean a person has an imbalance on an ongoing basis. However, you can find some clues in conventional lab work.

Again, histamine levels can be high (creating the intolerance) due to strong sensitivity (high release) and/or poor detoxification ability (where it builds up over time). Suboptimal Vitamin D and zinc (ideally measured through RBC Zinc) can also contribute to immune system dysregulation.

The easiest way to help a client to determine if they struggle with histamine intolerance is to do an experiment. I help my clients to implement a low-histamine diet for a full two weeks and also support them with DAO supplements with meals. If histamine is a challenge, they should experience significant relief. A low-histamine diet can be a challenge, but a client doesn’t have to implement it 100.0% in order to have a valid elimination trial and learn how their unique body responds. There are also some great supplements that can help while looking for the root cause.

These ideas can help to bring some substantial relief while getting to the root cause of my clients’ challenges. Sometimes my clients have histamine intolerance simply because of genetics such as impaired methylation or impaired production of DAO or HNMT. Supplements can be an easy way to overcome the detriment of genetics. However, most people struggle with histamine intolerance between of a basket of interconnected imbalance in the body that we can in time, help them to resolve. Common contributors include, low adrenal function (specifically low cortisol which typically promotes more Th2 hyper-reactivity to external threats), microbial imbalance/overgrowth in the gut (aka dysbiosis), too much overall protein intake, insufficient levels of key immune system nutrients (e.g. Vitamin D, Zinc, Copper, B vitamins), toxic environment/burden, chronic stress or lack of sleep, and believe it or not, chronic long-term use of antihistamine drugs (which over-ride the body’s natural regulatory systems and create more sensitivity).

Hope you found this blog helpful. Let me know if you need any additional help.


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