October 15, 2014 9:00 pm


Infections, histamine intolerance, and mast cells share a crucial connection often overlooked as a source of histamine intolerance.

Mast cells are commonly associated with allergic and even anaphylactic reactions, but their role extends far beyond that. These cells are vital in identifying and combating pathogens like bacteria, viruses, parasites, and fungi.

They are strategically located throughout the body in areas exposed to the external environment, such as the skin, airways, and gut, making them among the first to encounter pathogens.

Equipped for this life-saving task, mast cells are packed with mediators, including histamine, which are released upon detecting infections.

In fact, infections are an extremely common underlying cause of histamine intolerance in my client base, and mast cell activation that I encounter in my client base.

histamine, mast cell activation, fungal, candida, bacteria, parasite, bacterial, viral infections


Mast cells identify pathogens.

When they do, they release inflammatory mediators, attracting more cells to the infected area. For example, histamine increases blood flow and makes blood vessels leakier.

This leakiness allows other mediators to reach the site. There, they join with free radicals to fight the infection.

Bacterial Infections

Mast cells identify molecules on the surface of bacteria. These molecules bind to receptors on mast cells, triggering the release of inflammatory mediators like histamine.

Additionally, mast cells release other molecules, which can directly kill bacteria.

Viral Infections

For viral infections, the process works similarly.

Viruses activate mast cells through a specific cell surface receptor. This activation triggers the release of mediators, which prompt an antiviral immune response.

Parasite Infections

The same principles apply to parasitic infections.

Mast cells in tissues targeted by parasites, like the skin and gut, have receptors that identify parasites.

When activated, mast cells release inflammatory mediators, triggering an immune response to eliminate the parasites.

Fungal Infections

Similarly to parasites, fungi enter the body through mast cell-rich organs like the skin, gut, and airways. Mast cells have receptors that recognize fungi and trigger antifungal responses.

Additionally, mast cells produce several molecules that help protect the body against fungal pathogens.

Food Intolerances

The gastrointestinal tract and skin contain the highest concentration of mast cells.

During an infection, mast cells rapidly increase in the gut.

As they interact with infections, the mast cells release more inflammatory mediators, including histamine. When the histamine load exceeds the body’s ability to break it down, histamine intolerance occurs.

Studies also show a strong link between infections and food intolerances. For example, if your gut is colonized with Candida, you’re more likely to become sensitive to foods.

This sensitivity arises from the increased number of mast cells and the leakiness of the gut lining. This leakiness allows more food antigens to enter the bloodstream, leading to allergies and intolerances.


It is crucial to test for infections if you have histamine intolerances or mast cell activation.

Infections can increase the histamine load and trigger mast cells, potentially playing a significant role in your symptoms.

By understanding the powerful link between infections, mast cell activation, and histamine intolerance, you open up new and effective paths for restoring health.

Identifying and addressing underlying infections can reduce the histamine load and calm mast cell activation, bringing much-needed relief from intolerance and allergy symptoms. This proactive approach not only enhances your immediate health but also boosts your overall well-being.

In my client base, infections are present in each and everyone of my clients with histamine intolerance and mast cell activation.

To learn more about how bacteria causes mast cell activation check out my blog post Bacteria and Mast Cells: Rethinking Mast Cell Activation. 

Follow me on Instagram and Facebook to continue the conversation.

Additional Reading