Frequently breaking out in hives, flushing skin rashes? Have regular hay fever, headaches, nausea or diarrhoea? Can’t work out why or what’s going on?

You may have a histamine intolerance….

Here’s what was happening to Joanna – patchy red blotches at the slightest provocation or scratch, a frequent red rash on her neck, chest, arms and back that lingered for hours to days to weeks. Regular headaches and hay fever and occasional nausea and stomach cramps. Being in her twenties, it constantly embarrassed and annoyed her. She wanted it fixed ASAP.

Sound like anyone you know?


Why do histamine intolerances occur?

Histamine intolerance occurs when there’s a turning down of your body’s mechanisms that metabolise histamines. So, your histamines build up, similar to water backing up in a blocked sink. Their slower breakdown means the load of histamines you can handle is reduced.

My job is to help clear that blockage.   


What are histamines?

Histamines are natural amino acids found in fermented or aged food and beverage products. Histamine is also naturally produced in the body and is used to signal immune activity.

Common food sources of histamine are aged cheeses, aged fish products (smoked, tinned), preserved meats, berries, citrus, cocoa, spinach and eggs. Alcohol also contains a small amount of histamine, however alcohol worsens histamine intolerance symptoms due to blocking the metabolism of histamine.

Do you get hay fever like symptoms after red wine and aged cheese? Now you know why..


Signs and symptoms of histamine intolerance?

Often similar to allergic symptoms like hay fever, skin rashes, airway constriction, nausea, vomiting, diarrhoea, headaches and fatigue.


Timing and onset of histamine intolerance symptoms.

Symptoms of histamine intolerance manifest in response to the total amount of unmetabolised histamine within the body. For example, if you consumed a large amount of histamine rich foods over a short period of time you may experience symptoms within minutes of consumption, however if you consumed smaller amounts of histamine more frequency over a longer period of time you may experience symptoms several hours after ingesting dietary sources of histamine.


The difference between intolerance and allergy?

An intolerance is dependent on the amount of a substance as opposed to an allergy where it’s the mere presence. So, an intolerance is similar to a bucket, where you have a threshold at which you react.

Which is why intolerance symptoms are inconsistent because your histamine load will determine symptom frequency and onset.


Healthy histamine metabolism.

Histamine is normally metabolised by a specific histamine enzyme found in the gut, known as diamine oxidase (DAO).

Deficiencies in DAO inhibit the body’s ability to break down dietary histamine, resulting in excessive levels of histamine in the body.

Several factors can inhibit DAO, including alcohol, some medications such as antidepressants, anti-pyschotics and blood pressure medications.

Compromised DAO occurs from poor gut barrier health. Onset of histamine tolerance may coincide with an event that has disrupted your gut barrier function, such as stress, inflammation or infection.


Treatments to reduce histamine intolerance and improve DAO production.

Goal is to regain the ability to tolerate dietary histamines.

Histamine avoidance is necessary to reduce acute symptoms alongside addressing the drivers of gut dysfunction including stress, infection, dysbiosis and nutrient deficiencies.

Improving gut health will enhance DAO production alongside ensuring adequate levels of nutritional cofactors, vitamin B6, vitamin C, zinc and copper.

Bacteria within your microbiome can assist histamine metabolism, however, bad gut bacteria may produce histamine and thus exacerbate histamine intolerance symptoms.

Natural compounds such as quercetin enhance histamine metabolism.

Before reintroduction of histamine foods need to address diet, enzymes, bacteria and barrier. Reintroduction is necessary to allow patients to consume a range of nutritious foods and enjoy their quality of life.


Click here for a 20 minute podcast on Histamine Intolerance with Laurence Katsaras interviewing Naturopath and Researcher, Joanne McNeil (courtesy Metagenics Australia)

Understanding and knowledge can help you feel empowered to regaining your health, but can feel overwhelming if you didn’t major in biology or biochemistry.

Need help applying all this knowledge to your body in an easy and doable way? I’m here if you need a guiding hand or have any questions. Click here to book online.

If you know anyone who would benefit from this information, please share it.

Julie xo (Feeling Great Naturopath, Mt Martha)