In addition to this, there is another powerful way your diet can impact your histamine intolerance, and act directly on your brain. Research has shown that a compound called nitric oxide (NO), which you can find in food, can help to inhibit the production of histamine directly in the hypothalamus14.
How is histamine broken down? In the CNS (Central Nervous System) histamine is broken down by HMT (Histamine Methyltransferase) enzyme. This means that impaired methylation can contribute to high histamine levels. In some cases, methylated B vitamins and supplements such as DMG and TMG can help reduce histamine levels.
Antihistamines block cells from seeing histamine and can treat common allergies. Medicines like steroids can calm the inflammatory effects of allergies.
Natural antihistamines may help you control your seasonal allergies. Common ones are stinging nettle, vitamin C, quercetin, butterbur, bromelain, and probiotics. Some alternative practices—such as acupuncture, nasal irrigation, and exercise—may also help you manage symptoms.
For these people, histamine builds up in the body and is not broken down correctly. This can trigger an immune system response resulting in symptoms such as diarrhea, shortness of breath, headaches, or skin irritation.
If you're experiencing a histamine reaction, try chewing on fresh ginger or pouring boiling hot water over sliced ginger to make fresh ginger tea. In general, you can also drink ginger tea before bed to act as a natural antihistamine and prevent histamine reactions.
Diamine oxidase (DAO) supplements are over-the-counter products that restore the diamine oxidase enzyme in your body. They help break down histamine-rich foods and may reduce symptoms of histamine intolerance.
Foods which are reported as having lower histamine levels include most fresh produce, fresh meat, certain fresh/frozen fish, eggs including quail eggs and most fresh herbs.
Claritin and Zyrtec are effective and safe for most people with minor allergies. However, as with all medications, there may be some side effects. Loratadine—present in Claritin—may not be safe for people with severe liver conditions.
Studies suggest that vitamin B12 can trigger histamine release in the body. Certain bacteria or yeasts can convert histidine into histamine in the body, triggering an allergic reaction. Fermented foods high in certain types of microorganisms can trigger a histamine allergy in the body.
Histamine intolerance (HIT) is assumed to be due to a deficiency of the gastrointestinal (GI) enzyme diamine oxidase (DAO) and, therefore, the food component histamine not being degraded and/or absorbed properly within the GI tract.
Histamine and stress
While stress itself doesn't actually cause allergies, the chemicals released into your body as a result of stress increases the production of histamine, this in turn aggravating the symptoms13.
Histamine is an endogenous biogenic amine classically associated with peripheral allergic and inflammatory reactions but it can regulate both brain inflammation1 and neurogenesis2,3.
Histamine may contribute to brain diseases or disorders
Whether from neurons or mast cells, histamine may participate in these processes by contributing to vascular changes, alterations in the blood—brain barrier, changes in immune function or even cell death.
Magnesium is also needed to make the enzyme, DAO, which mops up histamine when it's been released, if you can't make DAO, histamine levels in the blood increase 16. Histamine release from immune cells causes many of the symptoms of allergic responses to, for example, pollen and insect bites.
Vitamin B6 and Vitamin C, in particular, have been shown to reduce symptoms of seasickness and histamine intolerance.
The zinc chelator N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) inhibits the release of histamine, the production of cytokines, and the secretion of lipid mediators in mast cells, and zinc supplementation rescues these inhibitory effects.
High Histamine Foods
Fruit: Citrus fruits, strawberries, bananas, pineapple, pears. Vegetables: Eggplant, avocado, tomatoes, olives, beans.
Coffee contains histamines in low amounts, but for people who are sensitive to them, it contains plenty to get a reaction out of them. While the natural histamine content in coffee is low, some coffee processes can increase histamine levels.
Histamine levels are another potent downstream target. Allergic symptoms exacerbate during nighttime and plasma histamine levels exhibit nocturnal peaks.
When you're all stressed out, your body releases hormones and other chemicals, including histamine, the powerful chemical that leads to allergy symptoms. While stress doesn't actually cause allergies, it can make an allergic reaction worse by increasing the histamine in your bloodstream.
MCAS (mast cell activation syndrome) You often hear histamine intolerance and mast cell activation syndrome or MCAS used together or even interchangeably.