What is histamine?
Histamine is an amine which, among other essential roles in various tissues, acts as a neurotransmitter, a component of stomach acid, and a defense mechanism for threats including bacteria, viruses, and allergies. Histamine’s job when presented with a threat is to cause an inflammatory response, signaling to the body that there might be a problem. The inflammation brought on by histamine within the white blood cells where it is made and stored allow those same cells to find and address the threat more quickly.
The inflammation brought on by histamine, although critical within the immune system, can result in a wide range of unpleasant symptoms. The most widely recognized example would be the headache, itchy eyes, and/or red face you might experience when you have a seasonal allergy attack. These symptoms are a result of the inflammation caused by the buildup of histamine, which is why it is common to take antihistamine medications such as Benadryl for these types of attacks.
Less commonly recognized is an intolerance of histamine itself: but often, we find that it is the explanation for symptoms that have long gone unexplained.
What causes histamine intolerance?
As with many intolerances and sensitivities, the symptoms of histamine intolerance, not yet widely recognized as an entity by mainstream allergists, vary greatly and are often difficult to pinpoint. In addition to the histamine that we produce naturally, certain foods can aggravate the problem either by being rich in the chemical or by having histamine-releasing properties.
Histamine intolerance can occur when there is a buildup or excess of histamine in the body, and/or when an individual has a deficiency of diamine oxidase (DAO), the enzyme responsible for breaking down histamine. Possible causes of the imbalance include:
> Histamine-rich foods and drinks such as aged cheese, fermented foods, and wine
> Genetic mutations in which DAO is not sufficiently produced
> Leaky gut
> Deficiency of certain vitamins & minerals including magnesium and Vitamin D
> Certain medications including some anti-inflammatories and some anti-depressants
What are the symptoms of histamine intolerance?
Inflammation is at the core of all symptoms of histamine intolerance. Because histamine is found throughout the body (in the brain, the gut, the cardiovascular system, and the lungs, to name a few), symptoms vary depending on which receptors are being activated and in which tissues. Possible symptoms include:
→ Nasal congestion; sneezing; itchy nose
→ Pain in stomach; nausea
→ Indigestion; heartburn
→ Rashes; hives; itchiness; eczema
→ Itchy eyes; tearing
→ Irregular menstrual cycles; menstrual pain; cramping
→ Mood swings; anxiety
Histamine intolerance is unearthed in many cases when patients have some combination of the symptoms mentioned above, which have long gone misunderstood. If histamine intolerance or low DAO is suspected, testing can be done following a comprehensive consultation, after which point histamine intolerance can be addressed with a combination of directed enzyme therapy with DAO, a low-histamine diet, and correcting leaky gut or other root causes (if applicable).