Histamine Intolerance

Histamine intolerance is not a sensitivity to histamine but an indication that you’ve developed too much of it. You can be born with this condition or develop it as a result of your genetics, diet, or medications you take. Many foods contain high histamine levels, including alcohol, aged cheeses, and fermented products. Histamine is a chemical that sends messages to the brain, signals the release of stomach acid for digestion, and is released as part of the immune system’s response to an injury or allergic reaction. 

Contrary to what you might think (or have been told), the food is not actually the problem. The body has methods to break down histamine – after all, we didn’t evolve with refrigerators and preservatives! 

The first histamine-degrading subtance is an enzyme that is produced in the lining of the intestines, called diamine oxidase (DAO). Its primary job is to break down histamine in our food. If the gut wall is damaged in any way, or if there are certain nutrient deficiencies, this enzyme may not be produced in adequate amounts and the histamine may aggravate the gut, causing symptoms similar to irritable bowel syndrome, and is also absorbed into the blood stream. Once in the blood stream, histamine is normally broken down by another enzymatic process involving N-methyltransferase (HNMT) and eliminated from the body. 

Another common factor is under-methylation. Methylation is a complex biochemical reaction that is on-going in the body and involved in the metabolism of vitamins, hormones, neurotransmitters and more. Removing histamine requires methyl groups, and when histamine is high, these groups get depleted, which further exacerbates the problem. 

Histamine intolerance occurs when there is either too much histamine being ingested or liberated, or not enough being broken down—or both! Any inadequacy in the clearance mechanisms – either in the gut or in the blood stream – can cause the symptoms of histamine intolerance. 

How does Histamine Interact with Hormones? 

Women may notice that their tolerance (or intolerance) changes throughout their menstrual cycle, or disappear when pregnant. This is because of a number of different hormonal interactions. 

Progesterone, which is high in the second half of the menstrual cycle and very high during pregnancy, up-regulates DAO. This means more DAO, and more histamine breakdown early in the luteal phase (soon after ovulation) when progesterone is high. 

Oestrogen down-regulates DAO. So an excess, or relative excess of oestrogen is associated with increased histamine intolerance. Which is why some women can suddenly become histamine intolerant around menopausal age.

Some forms of hormonal birth control (those containing oestrogen) cause an oestrogen excess and progesterone deficiency – one reason some women do better on a progesterone-only contraceptive. 

Normally, your body regulates histamine by making it, and then by clearing it. . . It’s a fine balance between “histamine in” and “histamine out”. Histamine also boosts libido, which helps explain oestrogen’s effect on increasing sex drive, while antihistamines decrease it. 

During pregnancy, not only is progesterone very high, but the placenta makes large amounts of DAO. Women often report that histamine intolerance, allergies and food sensitivities improve during pregnancy. 

Things that can affect your DAO enzyme or histamine levels include: 

Gastrointestinal (GI) disorders: GI disorders like inflammatory bowel disease (IBD) can cause DAO deficiency.  Histamine intolerance usually stems from an intestinal issue. You may be more likely to develop histamine intolerance if you have a gastrointestinal disorder – to read more click on the Healthline link below. 

Genetics: You may have a gene mutation that causes your body to produce either less DAO or dysfunctional DAO. Talk to us instore about gene testing options

Medications: Some medications can temporarily block DAO functions or prevent production, including: phlegm reducers (such as acetylcysteine), antiemetics (such as metoclopramide), antiarrhythmics (such as propafenone), blood pressure medications, (such as dihyrdalazine), antidepressants (such as amitriptyline).

Diet: Histamine-rich foods can cause DAO enzymes to function improperly. Some foods can block DAO enzymes or trigger histamine release. 

Bacterial overgrowth: When your body is unable to digest food properly, bacteria grow, causing you to produce too much histamine. Typical DAO enzyme levels cannot break down the increased histamine in your body, causing a reaction. 

Symptoms of a histamine intolerance 

Histamine intolerance symptoms are nonspecific. That means they can appear like symptoms of other conditions. This can often make it challenging for doctors to diagnose. In a small 2019 study, participants experienced an average of 11 symptoms, with 96.8% experiencing more than 3 symptoms. 

Gastrointestinal (GI) symptoms are the most common and include:  digestive issues, abdominal pain bloating, diarrhea, constipation, flatulence, nausea, vomiting. While they may vary, other common reactions associated with this intolerance include:  headaches or migraine, nasal congestion or sinus issues, fatigue, itchy skin, hives, irregular menstrual cycle. 

In more severe cases of histamine intolerance, you may experience:  abdominal cramping, tissue swelling, high blood pressure, irregular heart rate, anxiety, difficulty regulating body temperature, and dizziness. 

How do you manage histamine levels with diet?  The best strategy may be to try eliminating foods you suspect that are adversely contributing to your health events to see if doing so helps or changes your symptoms. In a systematic review from 2021, many of the foods typically listed as high-histamine or histamine-triggering may not actually have this effect depending on the person. 

Foods to consider limiting A health-promoting diet contains moderate levels of histamine. However, some foods high in histamine can trigger inflammatory reactions and other negative health events.  The benefits of a histamine-limiting diet are still an uncertain field of study. More research is needed. Limiting these foods may help some but not others.  

Histamine-rich foods include: alcohol and other fermented beverages, fermented foods and dairy products, such as yogurt and sauerkraut, dried fruits, avocados, eggplant, spinach, processed or smoked meats, preserved fish, shellfish and aged cheese.  

Several foods can also trigger histamine release in your body, such as: alcohol, bananas, tomatoes, wheat germ, beans, papaya, chocolate, citrus fruits (commonly implicated, as are mineral supplements containing citrates), nuts, specifically walnuts, cashews, and peanuts, food dyes and other additives, fish and pork.  

Drinks that block DAO production include:  alcohol, black tea, mate tea, energy drinks.  

For people with histamine intolerance, alcohol commonly aggravates the problems, resulting in facial flushing, a blocked nose and may also cause headaches.  So if “wine & cheese” sets you off, this is a good clue to having a histamine intolerance.    

Foods to eat 

If you have histamine intolerance, incorporating low-histamine foods into your eating pattern can help reduce symptoms. There are several variations of low-histamine eating plans. It’s important that you consult a healthcare professional such as a dietician before you eliminate foods from your eating plan. 

Some foods low in histamine include:  fresh meat and freshly caught fish, non-citrus fruits, egg yolk, gluten-free grains, such as quinoa and rice, dairy substitutes, such as coconut milk and almond milk, fresh vegetables except for tomatoes, avocados, spinach, and eggplant and cooking oils, such as olive oil.   

For further information on food compatibility the Sighi list is very comprehensive. You can easily find this online, though we haven't included a link as many of them are to PDFs which can cause our newsletter to end up in your spam folder!

What can be done about Histamine Intolerance? 

Firstly, a consultation with a health consultant can help you determine the underlying cause.  While avoiding high histamine foods is a fast way to feel better, it is a very restrictive diet and difficult to maintain in the long term. Long term dietary restrictions are not advised, as this can lead to nutrient deficiencies. By addressing underlying issues, most people find that they are able to consume histamine foods.  Taking antihistamines (such as Quercetin) may help reduce short-term symptoms.   

Most people will have some kind of gut involvement – so identifying and correcting dysbiosis and/or small intestinal bacterial overgrowth (SIBO) is important. Avoiding food that may aggravate a histamine release such as gluten and A1 casein (dairy) is also helpful to support the healing phase. These common foods trigger histamine release. Most New Zealand milk is A1, but A2 milk is available at some supermarkets. 

For women with appreciable fluctuations in histamine intolerance associated with the menstrual cycle, an important strategy is to promote the healthy detoxification of oestrogen. Find out if you have genetic variants that mean that oestrogen clearance is compromised (COMT, CYP1A1, CYP1B1).  Ensuring adequate intake of vitamin B6 is important because this vitamin supports healthy progesterone metabolism and upregulates DAO. Food sources of vitamin B6 include meat, chicken, and sunflower seeds.

To read the full articles on Histamine Intolerance see the links below. 

www.healthline.com/health/histamine-intolerance 

www.medicalnewstoday.com/articles/322543#testing 

www.houseofhealth.co.nz/blog/could-you-have-a-histamine-intolerance