What is histamine intolerance?

Histamine is vital to the human body. It is needed for the production of stomach acid and is used as a neurotransmitter to communicate messages to your body from your brain. Histamine is also responsible for typical allergy symptoms such as sneezing, watery eyes, runny nose and nasal congestion.

However, problems can arise when there is too much histamine in the body. This can be caused by excessive consumption of histamine-rich foods or problems with the enzymes used to breakdown histamine in the body. If this occurs, allergic and pseudoallergic reactions may be experienced.

Diamine oxidase (DAO) is an enzyme responsible for the degradation of histamine in the digestive tract. Histamine intolerance occurs when there is a deficiency or inhibition of this enzyme. When this happens, the body is unable to degrade the histamine ingested from food fast enough and the symptoms of histamine intolerance will result.

Common Symptoms Include:

  • Headaches, including migraine headaches
  • Dizziness or vertigo
  • Gastrointestinal complaints (acid reflux, diarrhea, nausea, vomiting)
  • Fast or irregular heart rate
  • Low or high blood pressure
  • Menstrual pain, PMS
  • Nasal congestion
  • Dry nose
  • Asthma
  • Depression and anxiety
  • Hives, skin rash, eczema, psoriasis
  • Difficulty falling asleep
  • Fibromyalgia
  • Rheumatoid arthritis
  • Neurological conditions

What causes lowered levels of DAO in the body?

The DAO enzyme can be lowered in many ways. In some people, especially those of Asian descent, genetics can play a big role. A prime example of this is the facial flushing experienced in some people with alcohol exposure. Gut disorders such as SIBO, leaky gut, and inflammatory bowel diseases can also damage the gut and result in a DAO deficiency.

It is very important to work with a clinician who is knowledgeable in Histamine Intolerance to determine what the root cause of your illness is. When you fix the cause, your symptoms will be gone for good!

The most common causes include:

  • Small intestine bacterial overgrowth (SIBO)
  • Nutritional deficiencies: copper, Vitamin C, vitamin B6
  • Leaky gut syndrome
  • Genetic polymorphisms (common in people of Asian descent)
  • Gluten intolerance
  • High consumption of DAO-blocking foods
  • Inflammation from Crohn’s, ulcerative colitis, and inflammatory bowel disease)
  • Certain medications
    • Non-steroidal anti-inflammatory drugs
    • Antidepressants
    • Immune modulators
    • Antiarrhythmics
    • Antihistamines
    • Histamine (H2) blockers

Treating Histmine Intolerance

The good news is, treating Histamine Intolerance is pretty straight-forward! First, it is imperative to determine what the root cause of your intolerance stems from. Work with an experienced healthcare professional to heal your gut, remove aggravating factors and replace deficiencies.

While the root cause is being treated, remove high histamine foods from your diet along with foods that block DAO and those that release histamine for a period of three months (see the list of foods below). If necessary, you may be asked to temporarily take a DAO supplement to correct the deficiency.

The “safe” foods below do not interfere with histamine levels in your body and can safely be eaten during the treatment period.

Low Histamine “Safe” Foods

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

Foods to Eliminate on a Low Histamine Diet

Foods High in Histamine

  • Fermented alcoholic beverages (wine, champagne, beer)
  • Fermented foods (sauerkraut, vinegar, soy sauce, kefir, yogurt, kombucha, etc.)
  • Vinegar-containing foods (pickles, mayonnaise, olives)
  • Cured meats (bacon, salami, pepperoni, luncheon meats, hot dogs)
  • Soured foods (sour cream, sour milk, buttermilk, sour bread, etc.)
  • Dried fruits: apricots, prunes, dates, figs, raisins
  • Avocado
  • Most citrus fruits
  • Aged cheese, including goat cheese
  • Some nuts (walnuts, cashews, peanuts)
  • Some vegetables (eggplant, spinach, tomatoes)
  • Smoked fish and certain species of fish (mackerel, mahi-mahi, tuna, anchovies, sardines)
  • Processed foods of all types (preservatives are high in histamine)

Histamine-Releasing Foods

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

DAO-Blocking Foods

  • Alcohol
  • Energy drinks
  • Black tea
  • Mate tea
  • Green tea

If you would like to get tested for Histamine Intolerance, talk to your naturopath about testing your DAO and histamine levels in your body.

In health,

Dr. Nicole Hartman

About Dr. Nicole Hartman

Dr. Nicole Hartman is a naturopathic physician, a world traveler, a hiker, and a blogger. She focuses her practice in fertility and women's health and takes an integrative, evidence-based approach to healthcare.