Histamine is formed through the metabolism of amino acids. It’s an amine (1).
Various levels of histamine are naturally present in foods, particularly those high in protein or those that have been fermented. High histamine levels are found in foods like cheese, wine, sauerkraut, and bananas (2).
Frying foods is actually found to increase their histamine levels in the case of meats, seafood, and vegetables.
It is also naturally produced by the body, where it is stored in immune cells – mast cells. Histamine is then released from these mast cells during allergic or immune system response.
During any sort of allergic response, the immune system reacts by releasing these compounds to protect the body from anything it might deem as harmful – whether it is or isn’t.
When histamine becomes elevated in the body due to dietary intake, or an inability to properly break it down, people experience allergic symptoms: aggravation of asthma, histamine intolerance, and various food sensitivities.
At higher concentrations, ingested histamine is normally metabolized by the enzyme diamine oxidase (DAO). However, undegraded histamine in those with mast cell activation or reduced DAO activity may cause numerous symptoms mimicking those of an allergic reaction (3).
How is this tied to mast cell activation syndrome?
Histamine intolerance is a different subset of mast cell activation syndrome (MCAS).
They are considered one-in-the-same, and often confused. The key difference between the two is that whenever a person has MCAS, the mast cells produce many different mediators, not just histamine.
For many people struggling with associated symptoms, mast cell activation syndrome might be a more accurate representation of what is happening. MCAS, therefore, might contribute to what many people deem “histamine intolerance.”
While histamine is the major component of MCAS, it’s only one single component.
Those with inflammatory bowel disease (IBD), ulcerative colitis (UC), and anorexia nervosa are found to have reduced or impaired DAO activity.
Individuals with histamine intolerance might directly benefit from antihistamine medication or DAO supplements – but the first line of treatment would be strict adherence to a histamine-free diet, along with supplements that support histamine degradation.
How does histamine intolerance and mast cell activation trigger food reactions?
Mast cells are an inherent part of your immune system.
Whenever people are exposed to potential allergens, including foods, mast cells react by releasing chemical mediators.
These “mediators” can cause the symptoms (mimic the symptoms) commonly associated with histamine intolerance, including triggering asthma. They are extremely similar to the symptoms associated with an allergic reaction.
If you have mast cell activation syndrome (MCAS), mast cells are overly active – meaning they respond to things they shouldn’t (like certain foods higher in histamine).
If you also have impaired ability to break down histamine due to impaired DAO, you have a recipe for MCAS or histamine intolerance, triggered by a number of foods. Excess histamine continues to trigger mast cells through their histamine receptors (4).
Responses to food are referred to as “secondary activation” as they are a result of exposure to external stimuli.
Conditions commonly associated with MCAS
Considering MCAS is an immune system mediated condition, with inflammation at the root, it has been associated with a number of chronic health conditions – that Candida overgrowth or IBS might actually be a result of MCAS (5). That means treating MCAS can effectively eliminate many related immune conditions.
Other conditions commonly associated with MCAS include:
- Irritable bowel syndrome (IBS)
- Celiac disease + gluten intolerance
- Candida overgrowth (fungal)
- Intestinal dysbiosis – the gut contains many mast cells and is home to the majority of your immune system
- Postural orthostatic hypotension (POTS)
- Gastroesophageal reflux (GERD)
- Rheumatoid arthritis
- Food intolerances and allergies (that weren’t there before)
If you’ve been diagnosed with one of these conditions, it’s just as likely that you have MCAS or a histamine issue underlying inflammation and immune response.
Healing MCAS and Histamine Intolerance
There are many paths to healing – and anyone who has experienced chronic illness understands this. Oftentimes, a multi-faceted approach is required to fully heal.
Generally, reliance solely on conventional prescription medication doesn’t allow healing. Instead, it works to mask the symptoms. Symptom relief does not equal cure, and often presents further issues down the line as anti-histamine medication (Benadryl, Zyrtec, Dimetane) merely encourages a more pronounced reaction when you taper off.
Unfortunately, healing from MCAS or histamine intolerance is not a simple process.
The major aspects of healing involve:
- Research and learning about MCAS, histamine, and how to heal naturally.
- Locating a practitioner that is knowledgeable in MCAS and compassionate. A practitioner will be able to test for specific triggers and other inflammatory issues to give people the best chance of recovery or healing.
Most people begin to notice improvement through:
- Dietary changes
- Avoiding any triggers
- Eating only nutritious, whole foods
- Healing the gut
- Targeting supplementation based on individual needs
- Supporting emotional wellbeing
What we suggest:
- Eliminate any potential mast cell triggers. These include food allergens like corn, gluten, casein (in dairy), and soy. Avoid fermented food for now. Comprehensive lists are available through a number of great online resources like Mast Cell 360.
- Poor sleep quality can increase mast cell activation. Unfortunately, MCAS and histamine intolerance might often be responsible for impaired sleep quality due to allergic or inflammatory symptoms.
- Optimize diet through nutrient dense, whole food. Food can trigger mast cells and histamine release, but food low in histamine and rich in antioxidants can help support recovery. Avoid food high in oxalates and glutamates.
- Pathogens can trigger or cause mast cell activation. Any gut or systemic infections would need to be treated before recovery – ideally, work with a medical practitioner that can identify any underlying infections.
MCAS and histamine intolerance can be healed
MCAS and histamine intolerance are two slightly different sides of the same coin.
Many people who experience “histamine intolerance” and find foods to be a primary trigger, may actually have an underlying case of MCAS. Conversely, the inability of the body to effectively break down histamine due to impaired DAO or immune system dysfunction may lead to overactive mast cells.
Working with a practitioner who understands mast cell activation and histamine is an important step in turning your health around.
There are a number of extremely thoughtful resources out there that can help to guide you on your path to recovery. Avoiding food and allergenic triggers, while supporting the health of your body through supplementation is essential.