For a quick health quiz, consider whether you suffer from any of the following symptoms:

  • Rashes / hives / eczema / psoriasis
  • Chronic headaches / migraines
  • Itchy eyes / runny nose / congestion
  • Premenstrual cramping or headaches
  • Profuse sweating
  • Food sensitivities / food allergies
  • Seasonal allergies
  • Asthma
  • Nausea / vomiting
  • Abdominal pain / chronic digestive disorders / loose stools
  • Irregular menstrual cycle / sever menstrual cramps
  • Chest tightness / rapid heart rate
  • Anxiety / irritability

These are very general symptoms and have many potential causes. One potential cause which isn’t discussed often is a condition called Histamine Intolerance (HIT)

Truly, there are not many issues that can cause so many problems in virtually every area of the body than histamine intolerance.

Instead, many patients with a combination of such symptoms are routinely referred to a variety of different doctors, each focusing on a piece of the puzzle:

  • Dermatologist
  • Gastroenterologist
  • Pulmonologist
  • Gynecologist
  • Endocrinologist
  • Psychiatrist
  • Cardiologist

Then, each doctor, in turn, prescribes a variety of medications:

  • Anti-inflammatories (cortisone, NSAID’s)
  • Antihistamines
  • Proton pump inhibitors
  • SSRI’s
  • Calcium-channel blockers
  • Hormones
  • Pain meds
  • Antibiotics

These medications suppress and mask the symptoms and not one of them addresses the underlying cause. In fact, some of them exacerbate the actual cause!

DID YOU KNOW: it is estimated that approximately 80% of individuals with histamine intolerance are women and most of them are over the age of 40.

What is Histamine?

Histamine is a natural chemical responsible for a few major functions. It is both made by the body and found naturally in certain foods. It conveys messages between cells and our nervous system. It is involved in the regulation of stomach acid, the permeability of blood vessels, muscle contraction and brain function and is essential to fight against disease-causing agents such as bacteria and viruses.

What is Histamine Intolerance?

Histamine only becomes a problem when we have metabolic disturbances that do not allow us to effectively metabolize histamine properly. In our body, histamine is broken down by the enzymes diamine oxidase (DAO) and histamine-N-methyltransferase (HNMT). DAO is responsible for breaking down histamine in the digestive tract and HNMT is responsible for breaking down histamine in the central nervous system, skin, lungs and other organs.

Histamine intolerance results from a disequilibrium between a cumulative build up of histamine and lower levels of DAO and HNMT. A deficiency in DAO brings about an acute form of intolerance while a deficiency in HNMT brings about a chronic form of histamine intolerance.

The onset and severity of histamine intolerance symptoms vary greatly between individuals, but common complaints are:

It’s not a Food Allergy!

With histamine intolerance, symptoms can be triggered by certain foods, but the mechanism is different than a food allergy.

  • Allergies are an IgE mediated, histamine response to an allergen, i.e., pollen or cat dander.
  • Histamine Intolerance is a toxic response by the body due to an excessive accumulation of histamine rather than an over-release of histamine. Thus, symptoms may not be immediate but may be triggered any time your “threshold” is reached and it may be difficult to pinpoint a particular food as the culprit.

It’s important to note that some of the symptoms mimic a true allergic reaction, but since histamine intolerance is not mediated by IgE, skin testing and blood allergy tests will be negative.

Possible Causative Factors for Histamine Intolerance

  • Over-the-counter and prescription medications that interfere with DAO and HMNT levels (including: antibiotics, antidepressants. antipsychotics, diuretics, muscle relaxants, pain meds, gastrointestinal meds, nausea and GERD meds,  malaria meds, tuberculosis meds, airway meds, heart meds, acetylsalicylic acid (aspirin), indomethacin (Indocin), diclofenac (Voltaren), and naproxen)
  • Genetic susceptibility (MTHFR, DAO, MAO, HNMT, PEMT)
  • Pathogens (a number of which produce histamine or block methylation)
  • Intestinal conditions (leaky gut, SIBO, IBD, IBS) or injuries that compromise the gut lining and affect digestion
  • Nutrient deficiencies (B12, folate, B6, B2, B1, zinc, copper, C, methionine) and nutrient demands (stress, anxiety, lack of sleep)
  • Diet (fermented foods, high protein intake, aged foods, leftovers, citrus, fish, histidine)
  • Hormonal insufficiency (adrenal fatigue) or excess (estrogen)
  • Lifestyle (alcohol, extreme or chronic stress, excessive exercise, low oxygen states)
  • Environment (high pollen counts, mold, mildew, dust mites, natural gas leaks)
  • Injury or trauma

Note that the three biggest factors involved with histamine intolerance include: leaky gut syndrome (or related disorders such as Crohn’s disease, Irritable bowel, celiac, gluten sensitivity, etc);  a genetic polymorphism with the DAO enzyme; and heavy alcohol and/or medication usage.

How Does Diet Play a Role?

Most people associate histamine with immune responses in the body. But almost all foods and drinks contain some level of histamine, and these usually increase as the food ages, spoils, or ferments.

Some foods and drinks also contain compounds that help release histamine in the body or block the production or effectiveness of the enzymes DAO and HMNT. Researchers are still working out how much histamine is in most foods and drinks, as well as precisely how some nutrients impair DAO and HMNT activities.

According to the current research, everyday foods and drinks rich in histamine include:

  • Fermented alcoholic beverages, especially wine, champagne and beer
  • Fermented dairy products such as cheese (especially aged), yogurt, sour cream, buttermilk, and kefir
  • Fermented or pickled vegetables, 
  • Kombucha
  • Fermented soy products including miso, tempeh and soy sauce
  • Fermented grains, such as sourdough bread
  • Cured or processed meats such as sausages, salami, and fermented ham)
  • Smoked, salted, or canned fish, such as sardines and tuna
  • Green tea, matcha tea, coffee, cocoa, chocolate
  • Nuts: walnuts, cashews, and peanuts
  • Vegetables: avocados, eggplant, spinach, and tomatoes
  • Vinegar, bouillon and broth
  • Junk foods or drinks that contain artificial colors or flavors

Foods that are suspected histamine liberators include:

  • All legumes (including peanuts) 
  • Citrus fruit, such as oranges, limes, lemons, and grapefruit
  • Pineapples
  • Bananas
  • Strawberries
  • Papaya
  • Cocoa
  • Egg whites

For additional tips related to diet, please refer to Histamine Compatibility list (PDF) by the Swiss Interest Group Histamine Intolerance (SIGHI).

People who may have histamine intolerance or are looking to reduce or reverse the condition will often need to go on a low-histamine diet. Usually, this means limiting the intake of histamine-rich foods rather than excluding them entirely.

People with histamine intolerance should also focus on increasing their intake of foods and drinks low in histamine such as:

  • Skinned fresh chicken, fresh or flash-frozen meat and fish
  • Cooked egg yolk
  • Most leafy greens except spinach
  • Most fresh vegetables (see exceptions above)
  • Most fresh fruits and berries (see exceptions above)
  • Gluten-free grains
  • Coconut and rice milk
  • Grass-fed butter
  • Most herbal teas except black, green, and mate tea

Scientists have found a number of nutrients that are effective at boosting DAO enzyme levels. These nutrients include:

  • Omega-3 and saturated fats
  • Vitamin B-6 (helps DAO break down histamine)
  • Vitamin C (helps lower histamine blood levels and help DAO break down histamine)
  • Copper (helps raise DAO blood levels slightly and helps DAO break down histamine)
  • Manganese (enhances DAO activity)
  • Zinc (helps DAO break down histamine)
  • Magnesium 
  • Calcium 
  • Phosphorus
  • Iron
  • Vitamin B-1
  • Vitamin B-12

Nevertheless, a low-histamine diet is a structured program that’s best done under the supervision of a nutritionist or a naturopath specializing in food intolerance.

Diagnosing Histamine Intolerance

Histamine intolerance is poorly understood in the medical world. Most health professionals are not trained on the topic, diagnosis is flaky at best, and the condition itself is difficult to treat.

In fact, many practitioners typically recommend a diet high in histamine containing foods.  This includes fermented foods which have incredible health benefits for those with adequate histamine metabolism.

You may want to discuss the following tests with your health practitioner:

  1. Advanced Intestinal Barrier Assessment (or AIBA).
  2. Genetic Test (MTHFR, MAO, HNMT, PEMT).

Treating Histamine Intolerance

Aside from dietary changes, there is no set treatment for people with histamine intolerance. Depending on their symptoms or the cause of the condition, most people benefit from the following functional approaches:

  • Following a low-histamine or histamine-free diet
  • Avoiding DAO blocking foods (such as alcohol, energy drinks, black tea, mate tea, and green tea)
  • Taking DAO enzyme supplements (note: DAO supplements do not get into your bloodstream and cannot increase your DAO levels internally. This means that supplementing with the DAO enzyme only helps you break histamine down that you’re  consuming.) 
  • Taking targeted vitamin and mineral supplementation
  • Switching prescription medications
  • Avoiding medicines associated with histamine intolerance, such as most anti-inflammatory and pain drugs
REMEMBER: it is best to think WHY, HOW and MECHANISM of various conditions rather than focusing on the ‘condition’ itself.
Ronit Mor, ND

Ronit Mor, ND

Ronit Mor, ND, is the founder of My Wellbeing Compass and Mor Wellness Concepts. As a naturopath and a clinical aromatherapist, her greatest passion is educating, empowering and inspiring people on their path to regaining optimal vitality and wellbeing. She is also an author, regularly contributes articles to different publications, and is a local and an international speaker. Clients seeking her out for health and wellness are interested in increasing energy and vitality, improving chronic conditions, shedding excess weight, and slowing down/reversing aging indications. She guides them on matters pertaining to nutrition, detoxification, plant medicine, stress management, and a variety of alternative healing modalities.