Do you experience unexplained headaches or anxiety? What about irregular menstrual
cycles? Does your face flush when you drink red wine? Do you get an itchy tongue or
runny nose when you eat bananas, avocados, or eggplants? If you answered yes to any
of these questions, then you could have a histamine intolerance.
Having a histamine intolerance can be very frustrating, because the symptoms often
feel like they come out of nowhere.
What is Histamine?
Histamine is a chemical involved in your immune system, proper 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 is what
helps you break down food in your stomach.
You might be most familiar with histamine as it relates to the immune system. If you’ve
suffered from seasonal allergies or food allergies, you may have noticed that
antihistamine medications like Zytec, Allegra or Benadryl provide quick relief of your
symptoms. This is because 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.
Histamine causes your blood vessels to swell, or dilate, so that your white blood cells
can quickly find and attack the infection or problem. This is 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 begins
to build up and you develop what we call histamine intolerance.
Because it travels throughout your bloodstream, histamine can affect your gut, lungs,
skin, brain, and entire cardiovascular system, contributing to a wide range of symptoms,
and often making a histamine intolerance difficult to pinpoint and diagnose.
Common Symptoms of Histamine Intolerance
● Headaches/migraines
● Difficulty falling asleep
● Hypertension
● Vertigo or dizziness
● Arrhythmia, or accelerated heart rate
● Difficulty regulating body temperature
● Anxiety
● Nausea, vomiting
● Abdominal cramps
● Flushing
● Nasal congestion, sneezing, difficulty breathing
● Abnormal menstrual cycle
● Hives
● Fatigue
● Tissue swelling
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
● 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
Foods to Enjoy If You Have A Histamine Intolerance
Whew! That was a long list. You might be wondering now what on earth you CAN eat,
so I’ve made a list of low-histamine foods as well. Remember that freshness is key
when you have histamine intolerance!
Low-Histamine Foods
● 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, avocado, and eggplant)
● Dairy substitutes: coconut milk, rice milk, hemp milk, almond milk*
● Cooking oils: olive oil, coconut oil
● Leafy herbs
● Herbal teas
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 breakdown,
the American Society for Clinical Nutrition found that DAO is the main enzyme
responsible for breaking down ingested histamine. So if you’re deficient in DAO, you
likely have symptoms of histamine intolerance.
Causes of Low DAO
● Gluten intolerance
● Leaky gut
● SIBO
● 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 (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 to Test for Histamine Intolerance
Elimination/Reintroduction
Remove the above high histamine foods for 30 days and reintroduce them one at a
time. Typically this is done by trying each food 3 times per day for 3 days and checking
for symptoms.
Blood Testing
I use a test through Dunwoody labs to test for histamine levels and DAO levels. A high
ratio of histamine to DAO signifies that you are ingesting too much histamine and that
you don’t have enough DAO to break it down.
Trial of DAO
If testing is unavailable to you, you could simply try a diet low in histamine and add DAO
supplementation at each meal (see more on this below). If your symptoms resolve, you
could have low DAO. You can also use a trial of DAO enzyme in supplement form.
However, treating the root cause is best.
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.
Address the Root Cause of Your Histamine Intolerance
The real key to overcoming histamine intolerance is to identify and treat the root cause
of the issue. Other common causes I see are leaky gut and gluten intolerance.