Is Histamine Intolerance Real?

How many times have you visited your doctor for advice and treatment for seemingly random symptoms? It could be gastrointestinal issues like IBS, bloating or constipation.

 

Maybe your skin has been acting up, breaking out in rashes, hives or eczema. Perhaps you have a chronic cough or runny nose, or find it difficult to breathe sometimes. And don’t forget the heart palpitations, low blood pressure and anxiety (1).

These symptoms are all seemingly unrelated. But, is there a chance that all of these random flare ups are linked? 

All of these symptoms and more can be the result of a histamine response. If they stick around for a long time or they come back frequently, there is a chance that you have histamine intolerance.

What is histamine

Histamine is a chemical found in the body that has been known to scientists for more than one hundred years. The effects of histamine in the body were first described by two researchers in 1910 (1).

Histamine is made and stored in high concentrations in secretory granules that are found in basophils, mast cells, gastric enterochromaffin cells, lymph nodes and the thymus  (1).

The role of histamine lies in various immune and physiologic mechanisms. Including the stimulation of the secretion of gastric acid, inflammation, the contraction of smooth muscles, vasodilation and cytokine production. It also acts as a neurotransmitter  (1).

The normal deactivation of histamine

When your body perceives that it is under threat from  bacteria, a virus or an allergen, the release of histamine is triggered. In turn it attaches to one of four different histamine receptor cells - H1, H2, H3 and H4. The effect of histamine depends on which receptor it attaches to (2). 

Once histamine has done its job, it should be quickly degraded by an enzyme called diamine oxidase (DAO). DAO enzymes are found mainly in the small intestine, ascending colon, placenta and the kidneys. DAO enzymes are particularly responsible for degrading ingested histamine - that which we get through food and environmental exposures. For this reason, individuals who are intolerant to high histamine foods often take a DAO enzyme supplement to achieve relief.

A second enzyme is also involved in the inactivation of histamine - histamine-N-methyltransferase (HNMT). It is more widespread in the body. It is found in the kidneys, liver, spleen, colon, prostate, ovaries, spinal cord cells and the trachea and respiratory tract  (1).

Both of these enzymes are involved in making sure that histamine levels are kept in check. But, DAO is most active in preventing the absorption of histamine into the blood. That means that when you eat foods that contain histamine, the histamine is neutralized in the intestine and not absorbed into the blood. The threat is successfully neutralized (3).

Histamine levels gone wrong

If everything works the way it should, the threat is neutralized and you move on with your life with no further discomfort. But, as with all things, sometimes things can go wrong.

Sometimes, the amount of histamine consumed is excessively high. Even in people who have healthy histamine degradation, the high concentrations can cause an extreme response. It is called histamine intoxication and the effects can last a few hours or up to one day (3).

Histamine intolerance is a medical condition in which the person has an imbalance between the amount of histamine consumed and the effectiveness of the inactivation of the chemical. So, histamine builds up and you develop symptoms based on which receptor it binds to (4). 

The reason that more histamine is available to be absorbed into the bloodstream is because there is either insufficient DAO and HNMT, or their ability to function normally is inhibited (4). 

The amount and function of these antihistamine enzymes can be influenced by many things. For example, you may have a genetic predisposition that determines how effective these enzymes are or the amount you are able to produce. It is important to remember that your genes load the gun, but your environment and behaviours pull the trigger. In other words, if you have a genetic predisposition, it can still be managed by healthy lifestyle behaviours (4).

Certain diseases, such as renal failure and chronic urticaria also predispose you to histamine intolerance. DAO enzymes rely on cofactors to work efficiently. If you have certain nutrient deficiencies such as vitamin B6, vitamin C, copper, and zinc, you may find that histamine levels start to rise. Histamine intolerance can also become a problem during periods of extreme stress  (4).

It should be clear by now that histamine intolerance certainly is real! But, what can you do to control it?

Avoiding common sources of histamine

I have already mentioned that histamine is released from cells within your body. This is referred to as endogenous histamine. It is released in response to the perceived threat to your health. There are many factors that cause the release of histamine from the mast cells. These include extreme temperatures, trauma, vibrations, alcohol and certain foods. Common foods that trigger the release of histamine include citrus fruit, strawberries and tomatoes  (3).

There are also exogenous sources of histamine. These are found mostly in the food you eat. The level of histamine present in foods increases with the age of the food. Foods that are produced using microbial fermentation have the highest levels of histamine. These include aged cheese, sauerkraut, wine and processed meat (5).

 

Understanding and avoiding sources of histamine can reduce levels to therefore help with symptoms. Get my free guide to histamine intolerance below, to better understand how to avoid histamine sources:

 

 

 

Histamine intolerance doctors and diagnoses

In your reading you have found some possible reasons for your mismatching symptoms. You are questioning whether histamine intolerance is real or if you are just reaching out of desperation. The scientific evidence is clear. Histamine intolerance is indeed real.

The first step you need to take in order to improve your symptoms to get a proper diagnosis. After all the doctors you have seen, you are probably wondering if this is possible.

 

Keep in mind, there isn't quite a 100% definitive test for histamine intolerance, however there are indicative tests. To begin with, you are able to eliminate other potential diagnoses through testing (for example, an allergy test would show that it is, indeed, not a true allergy to high histamine foods). Additionally, there are certain tests for histamine intolerance that can strongly indicate the likelihood of histamine intolerance being present, and provide you with a potential path to recovery.

As with the diagnosis of any condition, the process starts with a thorough medical history. Your doctor or healthcare professional needs to ask a lot of questions about your adverse reactions. They need to establish a definite link between your reaction and the consumption of histamine-rich foods and beverages (6).

The reaction also needs to be reproducible and recurring. In the case of histamine intolerance, there may be some coexisting factors such as IBS. These also need to be mentioned ( 6).

It is difficult to remember what you ate for breakfast today, never mind last week, Monday. That makes a food and symptom diary indispensable for making a diagnosis of histamine intolerance. You need to record everything you eat and drink, how much you consume and when you consume it. You also need to note when your symptoms occur and how severe they are  ( 6). My guide to histamine intolerance comes with a free food and symptom diary made specifically for this purpose, so I encourage you to get it below:

 

 

 

 

Low histamine diet for histamine intolerance

Now that you have a diagnosis of histamine intolerance you can take steps to improve your symptoms. It takes a bit of time, but the relief from your uncomfortable symptoms is worth it.

Research shows that following a diet that has a low histamine level and limits foods that may trigger the release of histamine, has a positive effect on histamine intolerance (7).

 

In fact, it's one of the fastest ways to get symptom relief and to understand if you're really histamine intolerant. If histamine is truly a trigger for you, within 1-2 weeks you'll begin experiencing symptomatic improvement simply by eating a true low histamine foods list. Click below to get the free low histamine diet and experience relief quickly!

 

 

Due to the diverse nature of the symptoms, histamine intolerance is often un-recognised or underestimated by both the patient and the doctor. But it is a very real condition with very real implications for your health and wellbeing.

 

To begin your journey, start a low histamine diet, keep a food and symptom diary and get a proper diagnosis. You don’t have to feel poorly all the time, and we're here to help!

 

Anita Tee, Nutritional Scientist

References

1. Comas-Basté O, Sánchez-Pérez S, Veciana-Nogués M, Latorre-Moratalla M, Vidal-Carou M. Histamine Intolerance: The Current State of the Art. Biomolecules. 2020;10(8):1181. 
2. Histamine - Molecule of the Month - JMol version - School of Chemistry - Bristol University [Internet]. Chm.bris.ac.uk. 2021 [cited 23 June 2021]. Available from: http://www.chm.bris.ac.uk/motm/histamine/jm/body.htm
3. Kovacova-Hanuskova E, Buday T, Gavliakova S, Plevkova J. Histamine, histamine intoxication and intolerance. Allergologia et Immunopathologia. 2015;43(5):498-506. 
4. Schnedl W, Enko D. Histamine Intolerance Originates in the Gut. Nutrients. 2021;13(4):1262. 
5. Maintz L, Novak N. Histamine and histamine intolerance. The American Journal of Clinical Nutrition. 2007;85(5):1185-1196. 
6. Reese I. Nutrition therapy for adverse reactions to histamine in food and beverages. Allergologie select. 2018;2(01):56-61. 
7. Jaros J, Shi V, Katta R. Diet and Chronic Urticaria: Dietary Modification as a Treatment Strategy. Dermatology Practical & Conceptual. 2019;:e2020004.