DAO degradation disorder and histamine intolerance

How are the enzyme DAO (diamine oxidase) and the biogenic amine histamine related? DAO is the main enzyme for breaking down extracellular histamine (e.g., from food) in the gut . If there is a HNMT breakdown disorder , however, the cause lies in the liver. It can therefore be deduced that the main cause of histamine intolerance also lies in the gut. But what factors and external influences restrict DAO synthesis? You can learn more about this, and whether DAO levels can be increased, in this blog post.

5 causes of a DAO or histamine degradation disorder

The effect is the same for everyone with a DAO (diamine oxidase) deficiency: there is too much histamine in the body , which can no longer be properly broken down and enters the bloodstream. This leads to symptoms typical of histamine intolerance, which vary in severity and include migraines, nausea, brain fog, itching, skin problems, fatigue, gastrointestinal issues, and diarrhea. However, the underlying causes differ from person to person.

DAO inhibitors : Drug substances, alcohol , or food additives can reduce DAO activity.
Disrupted hormonal balance : Not only estrogen dominance, but also thyroid disease, hormonal imbalance during menopause or puberty can lead to reduced DAO activity.
Damaged intestinal mucosa : Gastrointestinal diseases such as small intestinal bacterial overgrowth (SIBO), leaky gut or celiac disease cause inflammation in the intestinal mucosa and thus a DAO deficiency.
Nutrient deficiencies : To function optimally, DAO requires various nutrients such as vitamin B6, vitamin C, zinc, and copper. In some cases, a deficiency can lead to impaired DAO breakdown.
Genetic factors : There is also a genetically determined reduced DAO enzyme activity.

DAO inhibitor foods

DAO inhibitors are not only medications and synthetic food additives , but also certain foods that restrict the function of the DAO enzyme or cause a histamine overload. These include histamine-rich foods and biogenic amines such as serotonin, putrescine, and tyramine. These also require the enzyme diamine oxidase for their breakdown and are preferentially metabolized by the body, even before histamine. Foods that block histamine breakdown include:

papaya
cocoa
Coffee
nutmeg
green tea
black tea
Mate tea
Energy drinks
Strawberries
citrus fruits
nuts
tomatoes
salami
spinach
sauerkraut
Yeast

Determination of DAO activity

Is there a specific DAO test that indicates enzyme activity or the DAO level? Indeed, the enzyme's activity can be determined using the following tests :

DAO activity in the blood
DAO activity in stool
Histamine level in the blood
Histamine level in stool

An elevated histamine level in the blood (normal in cases of reduced DAO activity) can be an initial indication of impaired DAO degradation . The same applies to elevated histamine levels in stool.

How can the DAO enzyme be built up?

Is there such a thing as a DAO medication? Yes, there is. While taking it can certainly alleviate symptoms, this only applies to extracellular histamine from food and not to histamine liberators or the consumption of other biogenic amines. Likewise, the tablets have no effect on the body's own histamine, which the liver breaks down. Ultimately, taking any medication only alleviates the symptoms, not the underlying causes .

DAO enzyme food

However, there are not only foods that reduce DAO activity, but also those that contribute to increased DAO synthesis . First, make sure you consume only fresh and unprocessed foods , ideally organic . Since the nutrients vitamin C, vitamin B6, zinc, and copper in particular contribute to enzyme activity, consuming foods containing these nutrients is recommended. The following low-histamine foods can be helpful:

paprika
Kale
Brussels sprouts
broccoli
Blackcurrant
Parsley
rose hip
chicken meat
Fish
whole grain products
potatoes
lettuce
oatmeal
linseed
Brazil nuts
pumpkin seeds
poppy