The Definitive Guide to Diamine Oxidase Supplementation

Diamine Oxidase is a digestive enzyme and nutritional supplement that acts efficiently in our body by being able to treat the symptoms of intolerance to histamine, a natural compound that helps regulate specific functions of the digestive, nervous and immune systems. This compound is created by the body itself or introduced to it through all kinds of foods that have been fermented.

An accumulation of histamine can lead to diarrhea, headache, runny nose, asthma, hypotension, arrhythmia, hives, itching, redness of the skin, among other symptoms. Therefore, in certain cases, supplementation with this enzyme can make a difference if you want to treat the problems associated with suffering from this intolerance.

Find out everything you need to know about histamine intolerance and Diamine Oxidase supplementation .

¿Qué es la histaminosis?

What is Diamine Oxidase?

In the metabolism of histamine there is an important substance that is diamine oxidase. Also known as DAO for its acronym in English, it is a digestive enzyme produced in the kidneys, thymus, and intestinal lining of your digestive tract.

Its main function is to break down excess histamine in your body. That is, DAO keeps histamine levels in a healthy range to avoid uncomfortable histamine-induced symptoms. However, there is a percentage of patients who may have a DAO deficiency associated with their histaminosis, which would accentuate their problem of excess histamine .

¿Cómo funciona la DAO en el organismo?

What is histamine intolerance?

There are people who, no matter how much diet and exercise they do, do not stop gaining kilos, others notice an unjustified fatigue (almost exhaustion), and there are those who suffer from recurrent migraines. And, although they can be really bad, the blood tests do not show any notable disorder.

One possible culprit may be histamine intolerance , a medical condition that occurs as a result of elevated histamine levels. One of the suspected causes of this intolerance is DAO deficiency, because when your DAO levels are too low, it is difficult for your body to efficiently metabolize and excrete excess histamine. And the picture is worse if you eat a lot of foods rich in histamine.

¿Qué es la intolerencia a la histamina?

Physical symptoms of histamine intolerance

  • Nasal congestion.
  • Headaches
  • Itchy skin, rashes, and hives.
  • Sneezing
  • Asthma and shortness of breath.
  • Irregular heart beat (arrhythmia)
  • Diarrhea, stomach pain, and digestive upset.
  • Nausea and vomiting
  • Low blood pressure (hypotension)

Several factors can contribute to decreased DAO activity or histamine overproduction, including genetic mutations, alcohol consumption, certain medications, intestinal bacterial overgrowth, and consumption of large amounts of histamine-containing foods.

Consecuencias de la histaminosis

Diamine Oxidase (DAO) supplementation

DAO deficiency and histamine intolerance can be treated in different ways, even by supplementing with DAO. These supplements can relieve certain symptoms of histamine intolerance, such as headaches. However, it is important to recognize that several factors can affect the production of DAO and histamine in different parts of your body, so addressing the root cause of these problems is not as simple as replacing DAO with a supplement.

DAO supplements work to break down histamine that enters the body externally, such as food or drink. Taking this supplement will not affect internally produced histamine levels, as this type of histamine is broken down by a different enzyme called N-methyltransferase.

Efectos de la suplementación con Diamino Oxidasa

DAO Supplement Precautions

Thanks to research done on DAO supplements, no adverse health effects have been reported. However, such research is not yet sufficient, and therefore a specific dosage for this particular supplement has not yet been established.

Most of the available studies used doses of 4.2 mg DAO at a time up to 2 to 3 times a day just before meals. (Breda et al., 2015; Breda et al., 2018; Comas-Basté., 2018). So similar dosages are likely to be safe for most people, but that doesn’t mean it’s 100% risk-free.

Dosificación adecuada de DAO


DAO supplements cannot cure histamine intolerance or DAO deficiency, but they can alleviate symptoms by breaking down external sources of histamine, such as those in food and beverages.

Although more studies are still needed to verify the effectiveness, safety and dosage of DAO supplementation, currently there have been no adverse effects or problems when implementing it in the diet. However, it is important to consult your doctor before starting to include DAO supplements in your body.

Cómo tratar una reacción a la histamina


  • Breda, D., Burastero, S., Di Giocacchino, M. and Manzotti, G. (2015). Serum diamine oxidase activity in patients with histamine intolerance. International Journal of Immunopathology and Pharmacology. Doi: 10.1177 / 0394632015617170
  • Breda, D., Berti, A., Burastero, S., Colombo, G., Dagda, L., Mercurio, G., Ramírez, G., Saporiti, N., Yacoub, M. (2018). Diamine Oxidase Supplementation in Chronic Spontaneous Urticaria: A Randomized, Double-Blind Placebo-Controlled Study. Int Arch Allergy Immunol. Doi: 10.1159 / 000488142
  • Comas-Basté, O., Duelo, A., Izquierdo-Casas, J., Latorre-Moratalla, M., Lorente-Gascón, M. and Vidal-Carou, M. (2018). Diamine oxidase (DAO) supplement reduces headache in episodic migraine patients with DAO deficiency: A randomized double-blind trial. Clinical and Nutrion Journal. Doi: 10.1016 / j.clnu.2018.01.013