DAO deficiency is much more common than you might think and is caused by excessive consumption of some foods.
Some people may notice symptoms such as: migraine, hives or stomach pains that, despite being associated with food, the cause is often unknown.
One of the factors responsible for the appearance of these discomforts is the concentration of histamine in food.

Today we will focus on a recurring but rarely correctly diagnosed topic, the deficiency of the enzyme diamine oxidase (DAO). Throughout this article, we will reveal the causes, consequences, the foods involved and the importance of detecting them to avoid complications and what to do or what to eat if we have DAO deficiency.

DAO and histamine deficiency

Histamine intolerance is a disorder due to its reduced intestinal degradation, mainly caused by a deficiency in the enzyme diaminooxidase.

Histamine is present in most foods in varying amounts.

To go a little deeper into the subject, as we usually do, let’s carry out a physicochemical-physiological review of histamine.
Histamine is a bioactive amine or also known as biogenic amine, with essential physiological activities, which can also be found in some common foods in a wide range of concentrations.

Foods that contain histamine

• All fermented or matured products.
• Cheese
• Sausages
• Oily and canned fish are clear examples of foods with a significant histamine content.
• Seafood
• Meat if it is not very fresh, as the degradation of the product, as with fermentation, can increase the number or concentration of biogenic amines
• Alcohol because it blocks the enzyme
• Cocoa or chocolate
• Orange juice are the most common.

In short:

DAO – histamine ratio

Dietary histamine is primarily metabolized in the digestive tract by the DAO, which regulates its presence in the systemic circulation.
The deficiency of this enzyme could be one of the main causes of histamine intolerance, an alteration that translates into less intestinal degradation, and its subsequent increase in plasma.

Histamine intolerance (DAO deficiency) originates when there is an imbalance between the accumulation of histamine in the blood and the body’s ability to degrade it.

DAO deficiency can be congenital and the cause would lie in different genetic mutations in the gene found on chromosome 7q34-q36 that encodes an altered protein with low enzymatic activity DOI: 10.1097/FPC.0b013e328012b8e4; or acquired due to certain pathologies that limit the secretion of DAO, especially in inflammatory or degenerative intestinal disorders.
The third reason would be enzymatic blockade by some commonly used drugs such as analgesics (metamizole, acetylsalicylic acid); antihistamines (diphenhydramine, cimetidine, promethazine); antiarrhythmics (propafenone, quinidine); antiasthmatics (theophylline); antidepressants (amitriptyline, tranylcypromine) among others.

Other very important biogenic amines found in foods are histamine, putrescine, cadaverine, and phenylethylamine, which are produced by the decarboxylation of histidine, ornithine, lysine, and phenylalanine, respectively.
Purescine can also be formed by the removal of agmatine.
The production of these amines has been associated with yeast, Gram-negative and Gram-positive bacteria.
Thus, several species of yeasts, such as Debaryomyces hansenii, Yarrowia lipolytica, Pichia jadinii or Geotrichum candidum, have been described as potential producers. https://doi.org/10.1016/j.tifs.2014.07.007

Among the various multifaceted symptoms associated with histamine intolerance, headache is one of the most recognized and disabling consequences.
This is very important in our country due to the high consumption of cheeses and sausages, products that contain different concentrations of biogenic amines.
The enzymatic decarboxylation of tyrosine produces, for example, tyramine, the most abundant biogenic amine in dairy products, especially cheeses.
DOI:10.1007/s00217-002-0521-2

Histamine intolerance symptoms

The inability to break down histamine and its accumulation in the blood has side effects that can be reminiscent of an allergy.
Among these symptoms:

• Nervous System: Migraine and Headaches
• Digestive system: nausea, vomiting, abdominal pain, diarrhea.
• Skin changes: rashes, edema, localized swelling
• Osteopathic alterations: back pain and contractures.

Although some of the symptoms it causes can sometimes lead to confusion, DAO deficiency is not an allergy because the mechanisms that trigger them are different. In allergies, there is a complex mechanism involved, which aims to generate antibodies and there is IgE mediation.
In DAO deficiency, on the other hand, the symptoms do not occur due to the presence of antibodies, but because the body is not able to properly degrade the histamine present in the tissues. However, diagnostic errors are very common because foods rich in histamine can cause allergy-like symptoms, such as sneezing, hot flashes, itching, diarrhea, and even shortness of breath. https://doi.org/10.1111/j.1365-2222.1993.tb00287.x

Migraine is the most common cause of histamine intolerance

In an allergy, the immune system interacts, it is linked to the consumption of a specific product.
However, the accumulation of histamine is due to the release of this amine from various foods that cause histamine poisoning.
It is not linked to the consumption of a single food.
It is due to the consumption of a wide variety of foods that contain variable and even low levels of histamine.

Associated migraine

Migraine is a neurological and disabling pathology of multifactorial etiology that can have a negative impact on both family and work activity.
Its prevalence in the Spanish population has been estimated at 12%. https://www.sen.es/saladeprensa/pdf/Link278.pdf

Migraine is a type of headache but it can be accompanied by nausea, vomiting or sensitivity to light.

The pathophysiological mechanisms that underpin the onset of migraine are complex, but several pathways have been described to explain the association between histamine and headache.
In the nervous system, certain neurons synthesize histamine in the posterior basal hypothalamic nuclei, an area recently postulated as the site of various primary headaches due to the increased activity detected during the prodromal phases of migraine attacks.

The presence of migraines associated with DAO deficiency in our country is very important, due, in part, to the high consumption of sausages that, as is well known, have high levels of biogenic amines.

In one study, the objective of which was to determine the prevalence of DAO deficiency, patients with a confirmed diagnosis of migraine according to the current International Headache Society (IHS) and in subjects without migraine were considered.
A high incidence of DAO deficiency (87%) was observed in the group of patients with migraine.
On the other hand, 44% of the non-migraineural subjects had DAO activity levels below 80 HDU/ml.
Despite the multifactorial etiology of migraine, these results seem to indicate that this enzyme deficit could be related to the onset of migraine. https://doi.org/10.1007/s13105-017-0571-3

How DAO deficiency is treated

If a person is suspected of having a DAO deficiency, it is usual to carry out a blood test to detect the low concentration of the enzyme in question. If it is below 40 HDU/ml, there is a deficit. Once the diagnosis has been made and confirmed, the treatment is based on three fundamental pillars:

1. Identify the possible cause of this deficiency and treat it when possible (except if the origin is genetic).
2. Avoid alcohol and histamine-rich foods.
3. Take DAO supplements.
   In this case, if the patient knows that he will consume any of the trigger foods, he should take it first.
   In case the deficit is very pronounced, you should take the meals with the main meals.

Daosin® is a food for special medical purposes that is used in the dietary management of DAO deficiency.
It should be taken 5 to 15 minutes before meals.
By the time histamine-containing foods reach the intestine, the capsule should have already dissolved and the DAO enzyme it contains should be active.
The maximum daily dose is 3 capsules that should correspond to the 3 meals that contain histamine.
The contents of the capsule should not be chewed but swallowed whole, so that it passes intact through the stomach into the intestine.
If you have difficulty swallowing, you can open the capsule and swallow the contents with water.
It should not be crushed or chewed.

Conclusion

A failure in the function of this important enzyme (DAO) results in an imbalance of ingested histamine and the ability for its degradation.
Some clinical studies have correlated DAO deficiency with specific pathologies, mainly gastrointestinal diseases, dermatological diseases or migraine.

Today, one of the most efficient ways to treat DAO deficiency is through the consumption of supplements that help our body eliminate excess histamine.
That is why Daosin® is an excellent ally in people diagnosed with the aforementioned deficit.

Now that the holidays are approaching, prepare and anticipate the discomfort caused by copious lunches and excessive dinners.
Finally, we must not forget that it is important to maintain our habits of physical exercise, healthy eating rich in vegetables and fruits, and consumption of water instead of other types of sugary drinks, during the days when we do not have celebrations.
If we apply all these measures we will be able to enjoy these beautiful holidays without any undesirable symptoms.

This Christmas, if you want to prevent headaches, migraines and general discomfort, watch what you eat, but, above all, do not abuse alcohol.