Histamine intolerance – what is it?
Letzte Aktualisierung am 3. March 2026 von Dr. Michael Zechmann-Khreis
Histamine intolerance – definition
Histamine intolerance is a non-allergic food intolerance in which ingested biogenic amines (e.g. histamine, tyramine) are not sufficiently broken down in the body. The cause is usually a reduced activity of the enzyme diamine oxidase (DAO). Histamine N-methyltransferase (HNMT) may also be involved. Typical symptoms affect the gastrointestinal tract, skin and circulation and occur a few minutes to a maximum of 4 hours after eating. (cf. Reese et al.; 2021)
Causes of histamine intolerance
The causes are not fully understood. The following mechanisms are being discussed:
- Lack of nutrients: Copper and vitamin B6 are essential for DAO function, while vitamin C supports the breakdown of histamine.
- Reduced DAO activity: A lack of DAO, often caused by intestinal damage, can lead to histamine not being broken down sufficiently.
- Increased histamine intake: Histamine-rich foods such as mature cheese, wine or fermented products can increase symptoms.
- Intestinal bacteria: Certain bacteria in the gut can produce histamine themselves and thus contribute to the symptoms.
- HNMT inhibition: HNMT regulates histamine within the cells. If there is a disruption here, this can lead to a gradual accumulation of histamine.
So what exactly is this HIT?
Histamine intolerance, a reaction of the body to biogenic amines, can be classified into several categories. In the scientific literature, it is classified as a pseudoallergy on the one hand and as an enzymopathy or toxic reaction on the other. (Komericki et al., 2011; Zechmann-Khreis, M., 2025; Reese et al., 2021) This is shown in the following graphic overview:
(Zechmann-Khreis, M; 2025)
Symptoms of histamine intolerance
| Range | Typical symptoms |
|---|---|
| Gastrointestinal tract | Flatulence, diarrhea |
| Skin | Flushing, itching |
| Circulation | Dizziness, palpitations |
You can find a detailed list and classification of the symptoms here in this article.
Frequency of histamine intolerance
Histamine intolerance occurs in around 1-3% of the population. However, according to a study by the nmi portal, the number of unreported cases is very high, i.e. more people are probably affected. According to a study by Jarisch, around 80 % of those affected are women, most of them aged 40 and over. This trend could not be verified in the nmi portal survey.
DAO and pregnancy
Women repeatedly report that their histamine intolerance disappears during pregnancy and reappears after the birth. This is due to the fact that DAO is produced by pregnant women in very large quantities. The DAO is increasingly released into the bloodstream in order to protect the child from possible histamine excesses. (Velicky, P; 2018)
Differentiation from other diseases
Histamine intolerance is often confused with other diseases, including:
- Vagus nerve disorders: As the vagus nerve regulates numerous bodily functions, its symptoms can be very similar to those of histamine intolerance.
- Food poisoning: Excessive intake of biogenic amines can cause acute symptoms of poisoning.
- Mast cell activation syndrome (MCAS): Here, an excessive release of histamine by mast cells leads to similar symptoms.
- Food allergies: These are mediated by the immune system and must be excluded diagnostically.
Treatment and therapy
- Dietary adjustment: low histamine diet, preferably according to the 3-phase model
- Enzyme therapy: Taking DAO preparations can help to break down histamine. H1 antihistamines can also be used as support.
- Optimize nutrient supply: Supplementation of vitamin C, B6 and copper can support enzyme activity.
- Stress management: Chronic stress can disrupt the balance of the autonomic nervous system and exacerbate symptoms. Breathing exercises, meditation and moderate exercise can help.
You can find more information about the treatment of histamine intolerance in our “Therapy” section.
Histamine intolerance is a complex intolerance that is triggered by various mechanisms. An individual dietary strategy, targeted nutrient intake and avoiding trigger factors can help to alleviate the symptoms. Professional diagnosis and care by doctors or nutritionists is recommended in order to rule out other illnesses and initiate the right treatment.
Scientific classification
- Histamine is a biogenic amine.
Biogenic amines are broken down via DAO and HNMT.- Not only histamine plays a role, but also other biogenic amines.
- The evidence on histamine intolerance is heterogeneous.
- There are no internationally standardized diagnostic criteria.
FAQ on histamine intolerance
Histamine intolerance is a non-allergic food intolerance in which ingested histamine and other biogenic amines are not sufficiently broken down in the body. The cause is usually a reduced activity of the enzyme diamine oxidase (DAO), which breaks down histamine in the intestine. This results in non-specific symptoms such as gastrointestinal problems, skin reactions or circulatory symptoms.
No. Histamine intolerance is not a classic IgE-mediated allergy. In an allergy, the immune system reacts to an allergen. In the case of histamine intolerance, the problem arises from an imbalance between the histamine absorbed and its breakdown in the body.
There is no single, clearly validated laboratory test for reliable diagnosis. In practice, diagnosis is usually based on a structured medical history, a temporary elimination diet and a controlled reintroduction of histamine-rich foods. Laboratory values such as DAO activity can provide indications, but are not conclusive on their own.
Diamine oxidase (DAO) is an enzyme in the small intestine that breaks down ingested histamine. If its activity is reduced, histamine can enter the bloodstream and trigger symptoms. However, the level of DAO activity measured does not always correlate clearly with the severity of symptoms.
Biogenic amines such as histamine or tyramine are mainly produced through maturation, fermentation or prolonged storage. Typical histamine-rich foods are:
Matured cheese
Smoked or fermented meat
Sauerkraut
Canned fish
Alcoholic drinks, especially red wine
Individual tolerance can vary greatly.
The symptoms are varied and non-specific. Typical symptoms include:
Gastrointestinal tract: flatulence, abdominal pain, diarrhea
Skin: flushing, itching, hives
Circulation: dizziness, palpitations
General: headaches, tiredness
The symptoms often occur with a time delay after eating histamine-rich foods.
Sources
Zechmann-Khreis, M. “Understanding and mastering histamine intolerance”; MZK Verlag; 2025
P. Velicky, K. Windsperger, K. Petroczi, S. Pils, B. Reiter, T. Weiss, S. Vondra, R. Ristl, S. Dekan, C. Fiala, D. E. Cantonwine, T. F. McElrath, B. Jilma, M. Knöfler, T. Boehm, J. Pollheimer: Pregnancy-associated diamine oxidase originates from extravillous trophoblasts and is decreased in early-onset preeclampsia. In: Scientific Reports. Vol. 8, No. 1, April 20, 2018, doi:10.1038/s41598-018-24652-0.
Komericki, P., Klein, G., Reider, N., Hawranek, T., Strimitzer, T., Lang, R., Kranzelbinder, B., & Aberer, W. (2011). Histamine intolerance: Lack of reproducibility of single symptoms by oral provocation with histamine: A randomized, double-blind, placebo-controlled cross-over study. Wiener klinische Wochenschrift, 123(1-2), 15-20. https://doi.org/10.1007/s00508-010-1506-y
Reese, I., Ballmer-Weber, B., Beyer, K., Dölle-Bierke, S., Kleine-Tebbe, J., Klimek, L., Lämmel, S., Lepp, U., Saloga, J., Schäfer, C., Szépfalusi, Z., Treudler, R., Werfel, T., Zuberbier, T., & Worm, M. (2021). Guideline on the procedure for suspected intolerance to orally ingested histamine. Allergology, 44(10), 761-772. https://doi.org/10.5414/ALX02269
Sattler, J; Hafner, D; Klotter, HJ; et.al;“Food-induced histaminosis under diamine oxidase (DAO) blockade in pigs: Further evidence of the key role of elevated plasma histamine levels as demonstrated by successful prophylaxis with antihistamines“; Agents and Actions; Volume 27, Numbers 1-2 / April 1989