Histamine Intolerance and the Microbiome

Histamine Intolerance: How this potent chemical influences your microbiome

Are you curious if histamine intolerance could be at the root of your health concerns like chronic fatigue, irregular periods, anxiety, or headaches?

This article will explain what histamine intolerance is and how working to restore health in the gut microbiome can reverse these unwanted symptoms. 

What are histamines?

Histamine is a chemical that is naturally found in certain foods like fermented dairy, pickled vegetables, kombucha, alcohol, vinegar, canned fish, and many other food items. 

Histamine has many functions in the body and is most well-known for its role in allergic reactions. Individuals with food allergies have immune systems that mistakenly identify certain foods as a threat and start producing antibodies against these foods. When these antibodies bind to histamine-containing mast cells, it causes the mast cells to break down and release their stored histamine content.

The release of histamine causes allergy symptoms like hives, watery eyes, chest contribution, shortness of breath, and wheezing. The same mechanism occurs with environmental allergies, which is why the most well-known class of allergy medications is called anti-histamines. Yet, histamine's role in the body extends far beyond allergies.

Histamine acts as a neurotransmitter that plays a role in sleep disorders, schizophrenia, depression, mediates inflammatory reactions, and regulates stomach acid secretion. Histamines are even linked to menstrual cycle complaints. 

What is Histamine Intolerance?

Despite what the name projects, histamine intolerance is not necessarily when a person is intolerant to histamine, but rather there is too much histamine circulating in the body paired with an inability to break it down. 

The main enzyme responsible for breaking down histamine is DAO (diamine oxidase). With overconsumption of histamine-rich foods and improper function of the DAO enzyme, the body can become overburdened with histamines and respond with an array of symptoms that are categorized as signs of histamine intolerance.

These symptoms include, but are not limited to:

• Asthma

• Anxiety

• Hives

• Itching

• Diarrhea

• Chronic fatigue

• Nasal Congestion

• Headaches / Migraine

• Irregular Menstrual Cycle

The Histamine-Gut Microbiome Connection

Newer research shows that one of the main drivers behind histamine intolerance is a dysbiotic gut microbiome. That's no surprise here as more and more research emerges on how the gut microbiome plays a role in many inflammatory conditions, especially in relation to food allergies and sensitivities.

In order for the gut microbiome to be considered healthy, it must have four key factors: high diversity of bacteria, low levels of pathogens, a healthy mucosal lining, and an intact epithelial barrier.

With gut dysbiosis, there is often low diversity and an unhealthy balance of opportunistic and/or pathogenic bacteria to healthy bacteria. When these problematic bacteria are found in higher amounts, they eat away at the mucosal lining. This allows bacteria to reach the epithelial barrier and causes an immune response. The inflammation associated with this immune response breaks up tight junctions that hold the thin layer of epithelial cells together, causing increased intestinal permeability. Intestinal permeability has been found to increase sensitization to food proteins, which leads to food allergies.

Most of the DAO enzyme is also made in the intestines. If the gut is inflamed or damaged, the body may produce less DAO and lead to a build-up of histamine.

How do I Know if Histamine Intolerance is Impacting My Microbiome?

Working with a trusted provider is always recommended. They might have you start with an elimination diet and remove histamine-rich foods for 14-30 days to see if symptoms improve. You can also get a blood test check for DAO deficiency as some people have a genetic mutation in the DAO gene that does not allow for an effective break-down of histamine. Another way to diagnose histamine intolerance is through a skin prick test. A 2011 study using this method revealed a positive result in 79% of people with histamine intolerance. 

How to Reverse Histamine Intolerance to Help Restore Microbiome Health

Some people follow a low-histamine diet to find relief of symptoms, but this is often too restrictive and can lead to malnutrition long-term. This approach also does not address the root cause of why the body is releasing too much histamine or not breaking it down effectively.

Healing leaky gut is the most effective way to get to the root cause of histamine intolerance as mounting research demonstrates the role that dysbiosis plays in the development of allergies and elevated histamine levels. And, absence of gut inflammation is essential for the proper function of the DAO enzyme to break histamine down.

Healing leaky gut requires a multi-step approach that includes identifying and removing food intolerances, reducing stress, avoiding excessive exercise and supplementation with probiotics, prebiotics and other nutrients that help promote the growth of a healthy microbiome and repair damage to the mucosal lining.

Eating foods that the body mounts an immune response to, or lacks enzymes to properly digest, can also lead to increased inflammation. Removing known food intolerances for a temporary period of time is a key step in reducing inflammation while the gut heals.

Stress can change the composition of gut bacteria, and certain stress hormones have been shown to increase certain bacterial strains 10,000-fold in just 14 hours! This increase in pathogenic bacteria can then cause dysbiosis by crowding out beneficial bacteria. Excessive exercise has also been shown to cause intestinal permeability.

The use of spore-based probiotics has been shown in research to play a critical role in healing leaky gut. Spore-based probiotics improve microbial diversity and regulate the microbiome by competitively excluding pathogenic bacteria that are responsible for the break-down of the mucosal lining. They can also increase short-chain fatty acid (SCFA) production, which is necessary to rebuild the mucosal lining.

Prebiotics, or non-digestible oligosaccharides, are another vital feature of enhancing diversity. Certain oligosaccharides like FOS, GOS, and XOS have been shown to increase keystone strains like Akkermansia muciniphila, Faecauli prausnitzii and Bifidobacterium spp. when taken as a daily supplementation. These strains are effective in protecting against both allergies and inflammation.

If you suffer from seasonal, environmental, or food allergies, there's a good chance your body is burdened with excessive amounts of histamine. Addressing the root causes, which are often found in the gut is highly recommended.