Definition:

Histamine is an amine that is produced as part of a local immune response to cause inflammation. It also performs several important functions in the bowel and acts as a neurotransmitter or chemical messenger that carries signals from one nerve to another.

Histamine intolerance, affecting more than 1% of the population, results from disequilibrium of accumulated histamine and the capacity for histamine degradation. Histamine occurs to various degrees in many foods. In healthy people, dietary histamine can be rapidly degraded by histamine-degrading enzymes, diamine oxidases (DAO) or histamine N-methyltransferase (HNMT), whereas persons with low activity of DAO or HNMT are at risk of histamine toxicity.  Histamine is a substance in the body that has wide-ranging effects and impaired histamine degradation, and the resulting histamine excess may cause numerous symptoms.  It is a major chemical messenger involved in the allergic cascade of cell signaling.  There are receptors for histamine in the brain, stomach, skin, lungs, mucus membranes, and blood vessels.

Common Symptoms:

Allergic- like reactions: Nasal congestion, sneezing, asthmatic wheezing, hives, flushing, tissue swelling

Neurological: Headaches/migraines, vertigo or dizziness, difficulty falling asleep, easy arousal

Psychological:  Behavioral issues, anxiety, attention deficit disorders, or seasonal depression.

Gastrointestinal: Nausea, vomiting, abdominal cramps.

Cardiovascular: Arrhythmia, or accelerated heart rate, and hypertension

Other: Fatigue, difficulty regulating body temperature, abnormal menstrual cycle, etc.

Causes of high histamine levels:

Allergies (IgE reactions); bacterial overgrowth (SIBO); inflamed and leaky gut; gluten intolerance; under-methylation; diamine oxidase (DAO) deficiency; UV light and certain medications.

Causes of Low DAO

Genetic mutations (ABP1 and HNMT gene defects).

Gluten intolerance, Leaky gut, Dysbiosis in the Gut, Inflammation from Crohn’s, ulcerative colitis, and inflammatory bowel disease.

DAO-blocking foods: alcohol, energy drinks, and tea.

Medications: Non-steroidal anti-inflammatory drugs (ibuprofen, aspirin), Antidepressants (Cymbalta, Effexor, Prozac, Zoloft), Immune modulators (Humira, Enbrel, Plaquenil), Antiarrhythmics (propranolol, metoprolol, Cardizem, Norvasc), Antihistamines (Allegra, Zyrtec, Benadryl), Histamine (H2) blockers (Tagamet, Pepcid, Zantac).

Initial Foods to avoid:

Fermented alcoholic beverages, especially wine, champagne and beer; Fermented foods: sauerkraut, vinegar, soy sauce, kefir, yogurt, kombucha, etc.; Vinegar-containing foods: pickles, mayonnaise, olives; Cured meats: bacon, salami, pepperoni, luncheon meats and hot dogs; Soured foods: sour cream, sour milk, buttermilk, soured bread, etc.; Dried fruit: apricots, prunes, dates, figs, raisins; Citrus fruits; Aged cheese including goat cheese; Smoked fish, artificial preservatives and dyes, energy drink.

Other Foods to Avoid:

• Histamine-Rich Foods: Fermented alcoholic beverages, especially wine, champagne and beer; Fermented foods: sauerkraut, vinegar, soy sauce, kefir, yogurt, kombucha, etc.; Vinegar-containing foods: pickles, mayonnaise, olives; Cured meats: bacon, salami, pepperoni, luncheon meats and hot dogs; Soured foods: sour cream, sour milk, buttermilk, soured bread, etc.; Dried fruit: apricots, prunes, dates, figs, raisins; Citrus fruits; Aged cheese including goat cheese; Nuts: walnuts, cashews, and peanuts; Vegetables: avocados, eggplant, spinach, and tomatoes; Smoked fish and certain species of fish: mackerel, mahi-mahi, tuna, anchovies, sardines.
• Histamine-Releasing Foods: Alcohol, bananas, chocolate, cow’s milk, nuts, papaya, pineapple, shellfish, strawberries, tomatoes, wheat germ, many artificial preservatives and dyes, and some spices: cinnamon, chili powder, cloves, anise, nutmeg, curry powder, cayenne.
• DAO-Blocking Foods: Alcohol, energy drinks, black tea, mate tea, green tea.

Medications to avoid:

Non-steroidal anti-inflammatory drugs (ibuprofen, aspirin); antidepressants (Cymbalta, Effexor, Prozac, Zoloft); immune modulators (Humira, Enbrel, Plaquenil), antiarrhythmics (propranolol, metoprolol, Cardizem, Norvasc);  antihistamines (Allegra, Zyrtec, Benadryl); histamine (H2) blockers (Tagamet, Pepcid, Zantac).  Although histamine blockers, a class of acid-reducing drugs, seem like they would help prevent histamine intolerance, these medications can actually deplete DAO levels.

Treatment:

• Remove the suspected foods that may increase histamine.
• Diagnose and treat allergy-causing foods.
• Diagnose and remove environmental factors.
• If you’re on a medication that may be causing the intolerance, work with your physician to wean off of these medications.
• Fix the gut.
• Diagnose and treat undermethylation, including checking for genetic polymorphisms such as MTHFR.
• Certain supplements, such as some vitamins and minerals care helpful in reducing histamines.