What is histamine?

Histamine is a chemical involved in your immune system, your digestion, and your central nervous system. A neurotransmitter, it communicates important messages from your body to your brain. It is also a component of stomach acid, which helps you break down food.

You might be familiar with histamine in relation to your immune system. If you have seasonal or food allergies, you may notice that antihistamine medications for example provide quick relief for your symptoms.

Histamine’s role in the body is to cause an immediate inflammatory response. It serves as a red flag in your immune system, telling your body about any potential attackers. Antihistamines prevent this inflammatory response

Histamine causes your blood vessels to swell so that your white blood cells can quickly move in to resolve any problems. It’s part of the body’s natural immune response. Typically, enzymes will break down the histamine so that it doesn’t build up. If you don’t break down histamine properly, it builds up and up and you develop histamine overload and intolerance.

As histamine travels throughout your bloodstream, it can affect your gut, lungs, skin, brain, and your entire cardiovascular system. Histamine can contribute to a wide range of symptoms. This can make histamine intolerance difficult to pinpoint and diagnose.

Symptoms of histamine intolerance:

• Abdominal cramping and pain
• Abnormal menstrual cycle
• Anxiety
• Arrhythmia, or accelerated heart rate
• Diarrhoea
• Difficulty falling asleep
• Difficulty regulating body temperature
• Fatigue
• Flushing
• Headaches/migraines
• Hives
• Hypertension
• Nasal congestion, sneezing, difficulty breathing
• Nausea, vomiting
• Tissue swelling
• Vertigo or dizziness

Once formed, histamine is either stored or broken down by an enzyme. Histamine in the central nervous system is broken down primarily by histamine N-methyltransferase (HMT). Histamine in the digestive tract is broken down primarily by diamine oxidase (DAO).

Though both enzymes play an important role in histamine break down, DAO is the main enzyme responsible for breaking down ingested histamine. If you’re deficient in DAO, you likely have symptoms of histamine intolerance.

In addition to the histamine produced inside your body, there are also a variety of foods that naturally contain histamine, cause the release of histamine, or block the enzyme (diamine oxidase or DAO) that breaks down histamine, each of which can cause a build up of histamine.

What causes high histamine levels?

• Allergies (IgE reactions)
• SIBO, or Small intestinal bacterial overgrowth
• Diamine oxidase (DAO) deficiency
• Excess of histamine-rich foods
• Leaky gut

What causes low DAO enzyme status?

• SIBO – the bacteria in SIBO can degrade the DAO enzyme plus they can also produce histamine themselves, so a double whammy.
• Gluten intolerance
• Leaky gut
• DAO-blocking foods: alcohol, energy drinks, and tea
• Genetic mutations (common in people of Asian-descent)
• Inflammation from Crohn’s, ulcerative colitis, and inflammatory bowel disease.
• Medications:
  • Non-steroidal anti-inflammatory drugs (ibuprofen, aspirin)
  • Antidepressants
  • Immune modulators
  • Antihistamines
  • Histamine (H2) blockers

Histamine rich foods:

• Aged cheeses including goat cheese
• Cured meats: bacon, salami, pepperoni, luncheon meats, and hot dogs
• Dried fruit: apricots, prunes, dates, figs, raisins
• Fermented alcoholic beverages, especially wine, champagne, and beer
• Fermented foods: sauerkraut, vinegar, soy sauce, kefir, yogurt, kombucha, etc.
• Most citrus fruits
• Nuts: walnuts, cashews
• Peanuts
• Soured foods: sour cream, sour milk, buttermilk, soured bread, etc.
• Smoked fish and certain species of fish including mackerel, mahi-mahi, tuna, anchovies, sardines
• Vegetables: avocados, eggplant, spinach, and tomatoes
• Vinegar-containing foods: pickles, mayonnaise, olives
• Leftovers – the longer they have been kept the more histamine they will contain

Histamine releasing foods:

• Alcohol
• Artificial preservatives and dyes
• Bananas
• Chocolate
• Cow’s milk
• Nuts
• Papaya
• Pineapple
• Shellfish
• Strawberries
• Tomatoes
• Wheat germ

Low histamine containing foods:

• Cooked eggs
• Cooking oils: olive oil, coconut oil
• Dairy substitutes: coconut milk, rice milk, hemp milk, almond milk*
• Fresh fruits: mango, pear, watermelon, apple, kiwi, cantaloupe, grapes
• Fresh vegetables (except tomatoes, spinach, and eggplant)
• Freshly caught fish
• Freshly cooked meat or poultry
• Gluten-free grains*: rice, quinoa, corn, millet, amaranth, teff
• Herbal teas
• Leafy herbs

How do you deal with a histamine intolerance?

Firstly you can try and reduce the symptoms via diet (excluding the high histamine and histamine releasing foods) and taking certain supplements such as DAO.

The main thing though is to figure out the root cause as to why you have this build-up of histamine in your body. In my experience, it is usually down to poor gut health and an overgrowth of bacteria that can release histamine and degrade DAO, such as SIBO.

Feel free to contact me to arrange a free 15 minute discovery call if you would like to discuss how I can help with your histamine issues.