You might suddenly have histamine intolerance (HIT) because of a DAO enzyme deficiency, caused by genetics, medications, gut issues (like SIBO, IBD), or high histamine intake, which overwhelms your body's ability to break down histamine from foods, leading to allergy-like symptoms, often triggered by hormonal shifts (menopause) or new drugs. It's not a true allergy but a buildup of histamine, causing headaches, hives, digestive issues, or congestion.
Medical Conditions
Autoimmune disorders affect immune system function, which might lead to more histamine being released (11). Another condition causing elevated histamine levels is mastocytosis, rare disorder involving abnormal mast cell growth—the cells that make and store histamine (12).
Currently, the only evidence-based strategy for alleviating or preventing symptoms is adherence to a low-histamine diet, often supplemented with exogenous DAO to enhance histamine breakdown at the intestinal level [8,9,10,11,12,13,14,15,16].
The symptoms of histamine intolerance can be classified into two types: Direct: migraines, migraines, abdominal bloating after eating, diarrhoea, muscle cramps, deregulation of secretions (saliva, tears, vaginal discharge), abortions and infertility, among others.
Vitamin C. Vitamin C is a very common and well-known nutrient to strengthen the immune system and reduce inflammation. Vitamin C is also required to produce the necessary enzymes for the process of histamine breakdown, making it a vital anti-histamine nutrient.
It is also possible to develop asthma-like symptoms such as wheezing, shortness of breath, or bronchoconstriction (narrowing of breathing passages). Cardiovascular: In some cases histamine intolerance can cause low blood pressure that can in turn dizziness or fatigue.
Histamine-induced anxiety can feel like restlessness, a racing heart, palpitations, or a sense of unease.
Vitamin B 6: Often there is a deficiency
In studies and in practice, it was found that many affected people have histamine intolerance, a vitamin B6 deficiency. Some sources state that vitamin B6 is required for the synthesis of the enzyme dao and is involved in the breakdown process of histamine.
Many people believe they experience a “histamine dump.” This phenomenon usually happens at night when your body releases a sudden surge of histamine. A histamine dump can interrupt your sleep and cause headaches, flushing, itching, anxiety, and a racing heart.
An unbalanced and elevated quantity of histamine in HIT seems to be the main consequence of the ingestion of histamine-containing foods [2]. Predominantly, in HIT, the intestinal enzyme diamine oxidase (DAO) has a reduced ability to metabolize and degrade histamine.
Yes, magnesium helps regulate mast cell activity and can reduce histamine release. Does B12 stabilize mast cells? Yes, vitamin B12 supports nervous system health and may help stabilize mast cells, especially in MCAS patients with neurological symptoms.
When your estrogen levels rise, you release more of your own histamine. Histamine then stimulates your ovaries to release more estrogen - thus setting off a vicious cycle. In addition, estrogen stops your DAO from working well. If you are intolerant to histamine, you will not tolerate your own estrogen very well.
That would be for example a gastroenterologist if you have stomach or bowel problems, a dermatologist if you have skin problems, an allergologist or an immunologist, because they need to make sure that you don't have any other illness.
So if you suffer from histamine intolerance, you should prefer calmer sports such as strength training, Pilates or yoga. Interesting fact: Cardio training releases histamine and other inflammation substances, but the effect only takes temporary (up to 72 hours).
You might be surprised to learn that estrogen actually causes our mast cells to release more histamine. When estrogen is the highest (at ovulation and right before our periods), this is when it naturally causes our body to produce histamine. In the right amount, histamine is a good thing.
People with mastocytosis have an increased risk of developing a severe and life-threatening allergic reaction. This is known as anaphylaxis. The increased risk of anaphylaxis is caused by the abnormally high number of mast cells and their potential to release large amounts of histamine into the blood.
The role of vitamin B12 in histamine intolerance
Vitamin B12 supports the methylation process—a biochemical pathway that helps the body detoxify and regulate histamine levels. When B12 is lacking, methylation slows down, leading to higher histamine concentrations in the blood.
The Gut Microbiome and Its Influence on Histamine Levels
Dysbiosis is associated with histamine intolerance [3]. There may be an increase in histamine producing bacteria or a reduction in the enzyme diamine oxidase (DAO) that helps breakdown excess histamine.
Cortisol, a stress hormone, does not directly trigger histamine release. However, stress may exacerbate allergic reactions, possibly through the impact of cortisol on the immune system. Therefore, while cortisol doesn't directly cause histamine release, it can potentially influence allergic responses.
H1 and H2 antihistamines.
Taking antihistamines alone probably won't stop your symptoms, but it could help in combination with dietary changes. H1 histamine inhibitors include cetirizine, loratadine and fexofenadine. They usually treat allergy symptoms. H2 inhibitors include ranitidine and famotidine.
Omega-3 fatty acids (EPA and DHA) are known for their potential to support immune function and help manage inflammation. Using 3-5 grams of combined EPA and DHA daily may help manage symptoms associated with histamine overload.
Under your skin. Near blood vessels and lymph vessels. In nerves. In your lungs and intestines.
Histamine intolerance is a rather misleading name, as it refers to an excess of histamine in the body rather than a sensitivity to it. Maintaining the correct amount of histamine in the body is very important; a deficit of histamine can be deadly, while an excess causes symptoms harmful to the patient.
Histamine levels are another potent downstream target. Allergic symptoms exacerbate during nighttime and plasma histamine levels exhibit nocturnal peaks. In mastocytosis patients, peak levels of plasma histamine were observed in the early morning with the lowest in the afternoon (19).