Constantly experiencing problems like allergies, headaches, fatigue, itchy skin and rashes, or runny nose even though you are eating a healthy, real foods diet? The problem might be histamine intolerance, a condition which affects about 1% of Americans. (source) It is possible that even more people are suffering from histamine intolerance since the problem is so under-reported.
Here we will go over what is histamine, why the body might develop a histamine intolerance, symptoms, of histamine intolerance, foods which contain histamine, and histamine intolerance treatments.
What is Histamine?
We normally think of histamine as the chemical our bodies release during allergic reactions. Yes, this is one of the roles of histamines. But histamines also play many other important roles in our bodies:
- Fighting off foreign invaders (even when they are really harmless invaders like with mild allergic reactions)
- Acting as a neurotransmitter
- Regulating stomach acid production, muscle contractions, brain function, sleep, and more. Histamine even helps produce orgasms!
Histamine is mostly found in the skin, eyes, and stomach, hence why histamine is associated with problems like rash, watery eyes, and indigestion. Histamine is also found throughout the rest of the body too though, so it can cause a wide array of symptoms.
The body produces histamine from basophils (a type of white blood cell) and mast cells (a connective tissue cell). Histamine is then stored in white blood cells which circulate through the body and are activated if needed.
Histamine is found in many foods as well. The body also produces some histamine to digest food. “Normal” levels of histamine are about 0.3 to 1.0 nanograms per milliliter in blood plasma. Everyone has different tolerances for histamine though. (source 1, source 2
Symptoms of Histamine Intolerance
Diagnosing histamine intolerance based on symptoms alone is really difficult. Almost all of the symptoms which are associated with histamine intolerance could also be associated with some other condition as well.
In fact, if you go to a doctor with these symptoms, you will probably end up getting treatment for the symptoms or some other common ailment and not the underlying problem.
For example, if histamine intolerance is causing acid reflux, you might get proton pump inhibitors. (Learn why proton pump inhibitors are NOT the best way to treat reflux in The 30 Day Heartburn Solution) This is only compounded by the fact that few doctors and nutritionists are even aware that histamine intolerance exists.
The most common symptoms associated with histamine intolerance are:
- Skin problems like itchiness, rashes, and hives
- Swelling and inflammation
- Low blood pressure
- Fast heart rate
- Anxiety and panic-like symptoms
- Runny nose and congestion (which can lead to decongestant addiction like yours truly used to suffer with)
- Watery, red eyes
- Headaches and migraines
- Fatigue and lethargy, bad mood
- Digestive problems like upset stomach and reflux
UPDATE: Good news! There is now a histamine test that you can order directly without a doctor’s order! While I’m a HUGE fan of having a doctor’s guidance, I understand the need to know whether you have SIBO or not before you invest in a practitioner. You can order the test directly here.
What Causes Histamine Intolerance?
Histamine intolerance is caused when the body has more histamine than it can break down. Normally, the body is able to break down histamine using amine oxidases enzymes. Diamine oxidase (DAO) is the main enzyme in charge of breaking down histamine from food.
There are two main reasons your body might not be able to handle histamine:
- You are consuming too much histamine from food and/or
- Your amine DAO enzymes aren’t functioning properly
1. Food As a Cause of Histamine Intolerance
There are many foods which contain histamine. Consuming too many histamine foods can cause histamine intolerance. Note that histamine intolerance is very different from a food allergy though. With food allergies, there is a sudden release of histamine. With histamine intolerance, there is a gradual buildup of histamine in the body.
I like how Chris Kresser compares histamine intolerance to a glass of water overflowing.
When the cup is very full (high amounts of histamine in the diet), even a drop of additional water will cause the cup to overflow (symptoms activated). But when the cup is less full, it would take more water (histamine) to cause a response.
This is what makes histamine intolerance so difficult to diagnose. One day, you might be fine eating a certain food even though the histamine is gradually filling up your cup. But the next day, that food is the “additional drop of water” which overflows the cup, causing anabolic shock that sends you to the emergency room.
2. Amine DAO Enzymes as a Cause of Histamine Intolerance
If your amine DAO enzymes aren’t functioning properly, then you might not be able to handle even a little bit of histamine from food. (source)
What causes your amine oxidase enzymes to become impaired? Researchers still aren’t exactly sure but many believe that the problem lies in the gut.
If your digestive system isn’t functioning properly, you will have a lot of undigested food in the gut. Bacteria then work on this food, producing histamine. (source)
Certain antidepressant drugs called monoamine inhibitors (MAOS) are also to blame because they block amine oxidase enzymes and prevent histamine breakdown. People taking these drugs had all sorts of allergy-like symptoms. This is partly how researchers finally caught on to the problem of histamine intolerance.
Foods which Cause Histamine Intolerance
Before I give you a list of histamine foods, you must understand that food can cause histamine intolerance in various ways.
- There are foods which contain histamine
- There are foods which don’t contain histamine, but they get histamine from bacteria which feed on them (an example of this is meat which has been stored improperly). Note that even healthy bacteria (such as from fermented sauerkraut, pickles and kombucha) produce histamine.
- There are foods which trigger the body to release histamine
- There are foods which can block DAO, thus causing histamine intolerance.
The list of foods which contain histamine is really long. Quite frankly, it can be downright overwhelming. To make matters worse, good luck finding two lists of histamine foods which actually match! For example, some lists will say that citrus fruits are a no-go, whereas others say they are okay.
The reason for this discrepancy in histamine food lists is because everyone reacts to histamine in foods differently. Some people don’t have problems with citrus fruits but fermented foods might cause serious problems. (source) Unfortunately, customizing your list of histamine foods will require some trial and error as well as time and patience.
High Histamine Foods
- Alcohol (red wine is the worst offender)
- Other fermented beverages (this includes healthy beverages like kombucha too)
- Fermented vegetables (pickles, sauerkraut, etc)
- Most cheese
- Vinegar (although Apple Cider Vinegar seems to be less problematic)
- Processed meats like bologna and salami and, sadly, bacon
- Nightshade vegetables (tomatoes, eggplants, etc)
- Some spices (cinnamon, anise, chili, nutmeg, curry, cayenne, cloves)
- Leftover meat (because bacteria growing on it produces histamine; eat your meat as fresh as possible and store it carefully!)
- Fermented foods
Foods which Trigger Histamine Release
- Alcohol and other fermented beverages like kombucha
- Citrus fruits
- Dairy products
- Wheat germ
- Artificial dyes and preservatives
Foods which Block DAO
- Alcohol and other fermented beverages
- Tea (mainly green and black tea)
- Sugary soft drinks
How to Treat Histamine Intolerance
The good news is that you don’t have to suffer from histamine intolerance symptoms forever! The bad news is that it can be a bit tricky to diagnose histamine intolerance and you will have to be very careful about your diet for a period of time if you want to keep symptoms at bay.
Low Histamine Diet
The easiest method for diagnosing and treating histamine intolerance is to put yourself on a rigid low-histamine diet. You will need to avoid ALL foods which contain histamine, cause histamine to be released, or inhibit DAO. If your symptoms go away while on this strict diet, then you likely have histamine intolerance.
You don’t have to be on the low histamine diet forever. Remember, histamine builds up in the body over time. After a while of being on the low histamine diet, you’ll have hopefully purged some of the excess histamine from your body. You can start gradually reintroducing histamine foods back into your diet and see how you feel.
Remember that the body uses an enzyme called DAO to break down histamine. If your DAO enzymes are impaired, then you won’t be able to break down histamine and can develop symptoms.
There are some natural DAO supplements which can help improve DAO activity.
- Nigella Sativa Oil: This oil comes from black cumin seeds. It’s especially helpful if you’re dealing with congestion. The recommended dosage is 1tsp of the oil before eating in the morning.
- DAO enzymes: These are extracted from porcine kidneys. Take two capsules no more than 15 minutes before eating histamine-rich foods.
- Bromelain: This is a natural enzyme found in pineapple. Take one capsule daily.
- Quercitin with Bromelain: Quercitin is an antioxidant found in many plant foods. When combined with bromelain, it becomes an even more potent DAO-booster. Take two capsules daily.
- Ubiquinol CoQ10: Coenzyme Q10 is used for energy production in all of your cells and is important for many processes, including DAO activity. Ubiquinol is a reduced version of the coenzyme. Take one capsule daily.
The SIBO link
As with all complex health situations, histamine intolerance has several other components is closely linked to SIBO (small intestine bacterial overgrowth). Since gut bacteria producing histamine might be one of the causes of histamine intolerance, curing SIBO could cure your histamine intolerance. (source) You can take a breath test for SIBO thru Commonwealth Labs thru your health care practitioner. This is the test I took which confirmed my case of SIBO.
You can learn more about SIBO here.
Heal Your Gut
Why wouldn’t your body be producing enough DAO naturally? Researchers believe that a damaged gut might be to blame.
Foods like bone broth and gelatin are great for healing a damaged gut. You can find a recipe for how to make bone broth here.
As for gelatin, I recommend the Great Lakes brand of gelatin. Do not use those chemically-made and flavored packs of gelatin you find in supermarkets! They do not provide the same gut-healing benefits of real gelatin. You can buy Great Lakes gelatin here.
For more advice on how to use gelatin to heal your gut (along with lots of great recipes), I recommend you read The Gelatin Secret.
Eat Meals which Are Easy to Digest
Frustratingly, digestion itself causes the release of histamine. If you have a lot of histamine built up in your body, then the act of eating could cause problems – regardless of what you eat.
To prevent this, The Low Histamine Chef recommends eating a diet which is easy on digestion. She recommends that you get your nutrients from juicing, smoothies, and soups. These liquid meals require less gastric juices to digest and thus less histamine. I’m not normally a fan of juicing (read why), but this is one case when juice can help. Just go easy on the fruit so you don’t mess up your blood sugar regulation in the process! If juicing and other easy-to-digest meals are all you can handle for a while, don’t fret, it’s just the first step in your healing journey.
Probiotics can also help heal the gut and improve digestion. Unfortunately, most probiotics can also trigger histamine intolerance problems (remember, even healthy bacteria can produce histamine!). The exception to this is a probiotic called Prescript Assist (which you can buy here). It is made from a soil-based organism and does not cause histamine to be released.
What About Antihistamines for Treating Histamine Intolerance?
Antihistamines might be able to temporarily get rid of your symptoms and they’ve saved me of additional trips to the emergency room on more than one occasion but, in the long term, they are a bad choice for people with histamine intolerance. For more on this, read Why Antihistamines Aren’t a Good Treatment for Histamine Intolerance
Yes, I know that it is frustrating and adhering to the ultra-strict low-histamine diet is annoying. But be patient! Healing takes time. Once you remove the histamine buildup from your body and get your gut healthy, you will probably be able to start consuming some small amounts of histamine foods again.