What is Histamine?
Histamine is a chemical involved in your immune system, your digestion, and your central nervous system. As 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 the immune system. If you suffer from seasonal allergies or food allergies, you may notice that antihistamine medications 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, notifying your body of any potential attackers. Antihistamines prevent this inflammatory response. Histamine causes your blood vessels to swell, or dilate, so that your white blood cells can quickly find and attack the infection or problem. It’s part of the body’s natural immune response, and typically enzymes will break down the histamine so that it doesn’t build up. If for some reason you don’t break down histamine properly, it builds up and you develop what is called a histamine intolerance. Histamine travels throughout your bloodstream, so it can affect your gut, lungs, skin, brain, and entire cardiovascular system. Histamine can contribute to a wide range of symptoms, often making a histamine intolerance difficult to pinpoint and diagnose.
Common Symptoms of Histamine Intolerance
- Difficulty falling asleep
- Vertigo or dizziness
- Arrhythmia, or accelerated heart rate
- Difficulty regulating body temperature
- Nausea, vomiting
- Abdominal cramps
- Nasal congestion, sneezing, difficulty breathing
- Abnormal menstrual cycle
- Tissue swelling
So, what Causes High Histamine Levels?
- Allergies (IgE reactions)
- Bacterial overgrowth (SIBO)
- Leaky gut
- GI bleeding
- Diamine Oxidase (DAO) deficiency
- Histamine-rich foods
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 that breaks down histamine (diamine oxidase (DAO)). We will talk more about DAO and how you break down histamine in a bit.
If you have a histamine intolerance, I recommend avoiding the following foods until you have addressed the underlying cause of your histamine intolerance.
Foods to Avoid If You Have A Histamine Intolerance
- 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
- Most 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
- Cow’s Milk
- Wheat Germ
- Many artificial preservatives and dyes
- DAO-Blocking Foods
- Energy drinks
- Black tea
- Mate tea
- Green tea
Foods to Enjoy If You Have A Histamine Intolerance
That was a long list. Now you might be wondering what on earth you CAN eat, so I’ve made a list of low-histamine foods as well. Freshness is key when you have histamine intolerance.
- Freshly cooked meat or poultry
- Freshly caught fish
- Cooked eggs
- Gluten-free grains*: rice, quinoa, corn, millet, amaranth, teff
- Pure peanut butter*
- Fresh fruits: mango, pear, watermelon, apple, kiwi, cantaloupe, grapes
- Fresh vegetables (except tomatoes, spinach, and eggplant)
- Dairy substitutes: coconut milk, rice milk, hemp milk, almond milk*
- Cooking oils: olive oil, coconut oil
- Leafy herbs
- Herbal teas
*If you have an autoimmune disease avoid all grains, legumes, and nuts until you are able to successfully reintroduce them.
How Do You Break Down Histamine?
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), while histamine in the digestive tract is broken down primarily by diamine oxidase (DAO). Though both enzymes play an important role in histamine break down, the American Society for Clinical Nutrition found that DAO is the main enzyme responsible for breaking down ingested histamine. If you’re deficient in DAO, you likely have symptoms of histamine intolerance.
Causes of Low DAO
- 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.
- Non-steroidal anti-inflammatory drugs (ibuprofen, aspirin)
- Antidepressants (Cymbalta, Effexor, Prozac, Zoloft)
- Immune modulators (Humira, Enbrel, Plaquenil)
- Antiarrhythmics (propanolol, metaprolol, 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 in your body.
How Do You Treat Histamine Intolerance?
Relieve Your Symptoms Through Diet and Supplements
- If you have a histamine intolerance, step one is to minimize your dietary histamine by eating a low-histamine diet and avoiding foods that block DAO. You can also consider taking a DAO supplement, if available, for immediate relief. Speak to your health care practitioner about DAO supplements.
Address the Root Cause of Your Histamine Intolerance
- The key to overcoming histamine intolerance is to identify the root cause of the issue. Histamine intolerance is often caused by a gut health issue, particularly one called SIBO, leaky gut and gluten intolerance.