If you’re prone to itchy skin, hives, anxiety, dizziness, migraines, and/or stubborn gut issues (especially bloating and diarrhea), especially after eating foods high in histamine (think: tomatoes, citrus, spinach, pork, chocolate, cheese, fermented foods, etc.) …you may be dealing with histamine intolerance.
Histamine intolerance doesn’t just show up one day for no reason – and luckily, there’s a lot you (or your clients) can do about it! Read on to learn what I wish more people knew about histamine intolerance and gut health.
Disclaimer: This post was written for general educational purposes and should not replace 1-1 medical and dietary consultation with qualified healthcare providers.
Table of Contents
Wait… what exactly is histamine?
Most people think of allergies when they hear the word “histamine” – but the role of histamine in the body is actually a lot more complex (and not always a bad thing!).
Histamine is a type of bioactive organic compound and chemical mediator, which gets released by certain types of white blood cells (mast cells) in our gut and in other parts of the body, typically following the consumption of certain foods which may trigger the production of histamine. (We can also ingest histamine directly, from eating higher-histamine foods.)
Histamine is most often released from mast cells after eating certain types of foods (and also during an allergic reaction).
In healthy people, certain enzymes (diamine oxidase (DAO) / “histimase” and histamine methyltransferase) are released by our small intestine to break down the histamine.
However, people with histamine intolerance may be lacking in these enzymes (and/or prone to excessive mast cell activation and histamine production) and thus may experience symptoms of histamine overload.
What’s histamine intolerance?
Histamine intolerance is a type of chemical intolerance and disorder in which your gut isn’t able to efficiently and effectively break down and metabolize histamine from food. (1)
As a result, eating a seemingly “normal” diet (or especially a diet high in histamine from foods) typically results in “histamine overload”, a state in which there’s too much histamine being produced relative to what your body is clearing out.
Signs and symptoms
While this shouldn’t replace formal consultation or diagnostic criteria, and every case is unique, some of the most common signs and symptoms of histamine intolerance or overload (a state in which there’s too much histamine in your body relative to what you can clear out) may include any or many of the following (especially after eating, exercising, or even taking probiotics or certain other supplements) (1, 2)
- Dizziness
- Sneezing/rhinitis
- Nasal congestion
- Anxiety
- Bloating
- Diarrhea
- Abdominal pain
- Nausea/vomiting
- Redness
- Rosacea
- Hives
- Eczema
- Itchy skin
- Throat swelling
- Dyspnea (difficulty breathing), airway constriction
- Hypotension (low blood pressure)
- Tachycardia
- Headaches/migraines
- Numbness/tingling
- Heart palpitations
Common root causes of histamine intolerance
Everything happens for a reason– and this is most definitely the case for histamine intolerance. Knowing the unique root cause of your (or your clients’) histamine intolerance is important, because it can help you determine the best treatment interventions, which can vary case-by-case.
In my own case, I was born with a DAO gene variant, which means that for my whole life, my small intestinal brush border hasn’t produced as much of the DAO enzyme at baseline compared to people with normal DAO enzyme levels in their gut. This explains why I’ve always been more prone to allergies and symptoms such as itching, rhinitis and even oral allergy syndrome (to a certain extent).
In my clinical practice, clients most often develop or acquire histamine intolerance later in life, secondary to gut imbalances which include (but aren’t limited to) the following which may lead to upregulation in mast cell activation and/or a DAO enzyme deficiency (1):
- Inflammatory bowel disease (IBD)
- Celiac disease
- Small intestinal bacterial overgrowth (SIBO)
- Dysbiosis
- Fungal overgrowth
- Mold (mycotoxin) exposure (3)
- COVD-19 vaccination (4)
- High-stress and trauma (5, 6)
(IMO, this may explain in part why we’ve seen a big uptick in histamine issues since 2021. Just saying!)
What can you do about it?
While histamine intolerance is a burden, the good news is there’s a lot you can do about it to help mitigate unwanted symptoms.
Dietary modification
A nutritionally-balanced and varied lower-histamine diet (which reduces or limits foods high in histamine or histamine-liberating foods) can be a game-changer for many people with histamine intolerance, during the early stages of symptom management.
In cases of histamine intolerance co-occurring with IBS, I would also strongly advise reducing and limiting alcohol intake as much as possible. That’s because alcohol has been shown to compete with certain metabolites of histamine, and can stimulate histamine release from mast cells. (7)
Recommended reading: Can you drink alcohol with IBS, IBD, SIBO, or CSID? [Gut health dietitian insights, tips, & best practices]
However, long-term, I would recommend going beyond dietary modification for symptom management. This means addressing your inner terrain holistically with the right integrative health interventions, so your body can restore resilience and effectively digest and metabolize histamine from food.
Enzyme replacement & digestive support
For many people, supplementing with a DAO enzyme (about 5 to 15 minutes before meals) can go a long way to help improve oral tolerance to higher-histamine foods and histamine-liberating foods.
- Right now I’m personally leaning into a plant-based DAO enzyme supplement called Naturdao which is derived from peas.
Herbs and nutraceuticals
In addition to breaking down histamine with the right digestive enzymes, stabilizing mast cells (the white blood cells in your immune system, responsible for making and releasing histamine) can also help to reduce the histamine load on your body.
As a functional dietitian and clinical herbalist, herbs with histamine-modulating and/or mast cell stabilizing properties are my go-to.
Recommended reading: Best Herbs & Supplements for Allergies: Dietitian & Herbalist Picks
Nervous system regulation
As a dietitian and herbalist, I would be doing my clients a disservice if I didn’t acknowledge the importance of nervous system regulation– it’s what gives dietary interventions and herbal supplements legs to stand on.
Eating balanced meals at structured times (promoting stable blood sugar levels) each day is one of my favorite ways to help create safety in your nervous system– but I also endorse the following interventions:
- Prayer and deliverance
- Nerva
- Truvaga/Pulsetto
- Diaphragmatic breathing
- Gargling, humming, and other vagus nerve stimulation exercises
For more intensive nervous system regulation support, check out Shawna Pelton, Lindsay Mitchell, and Primal Trust.
Pharmaceuticals
Pharmaceutical drugs aren’t my first choice or personal cup of tea– but still, I’ve seen some of my nutrition clients get symptom relief via over-the-counter antihistamines such as Claritin, Pepcid, etc. (alongside other interventions, as needed).
Whether you opt for a natural dietary and herbal approach or a pharmaceutical path (or an integrative approach which includes both), make sure you’re consulting with your healthcare providers for recommendations tailored to your bio-individual needs and goals.
Hormone replacement therapy (HRT)- particularly estrogen– can also potentially exacerbate histamine overload in the body. Consult with a histamine-informed doctor who can help you in this scope.
Root-cause interventions
Don’t get so caught up in symptom management that you forget to identify and address the underlying root-cause culprits and any co-occurring conditions (such as those mentioned earlier).
Even from a symptom management standpoint, histamine intolerance often co-occurs alongside other types of food intolerances like FODMAP intolerance, fat intolerance, etc. Nothing exists in a vacuum!
Make sure you’re working with holistic healthcare providers who can help you (1) possibly layer a low histamine diet with other dietary modifications (like a low FODMAP diet) such as in cases of SIBO, and (2) identify the underlying issue(s) contributing to histamine intolerance.
- For example, if you have SIBO, make sure to look into a holistic SIBO treatment plan (which goes far beyond just the 2-week antibiotic prescription, so as to prevent it from recurring).
- On the other hand, your histamine treatment plan would look very different if you’re navigating another condition such as IBD, a mold exposure, or something else contributing to your histamine intolerance.
Key takeaways and final thoughts
Histamine intolerance is a growing modern-day epidemic in the world of gut health. This is because many contributing root-cause risk factors of histamine intolerance are going left unchecked in the conventional healthcare industry.
Stabilizing histamine overload is an important component of gut-healing, and it must precede any kind of antimicrobial or antifungal interventions.
A holistic approach to addressing and resolving histamine intolerance may include low histamine nutrition therapy, herbal and/or pharmaceutical histamine modulators and mast cell stabilizers, and nervous system regulation. However, it’s important to make sure you’re also addressing the underlying root cause(s) of your unwanted symptoms.
Next steps: Whole-istic Living Case Study Vault (join the waitlist)
For a limited time, I’m offering space for up to 20 founding members of the Whole-istic Living Case Study Vault for registered dietitians, nutritionists, and herbalists interested in learning evidence-based nutrition and herbal protocols that actually help people at the root-cause level.
In this membership program, I’ll be pulling back the curtain sharing the protocols (via a new case study each month) that worked for my clients with incredible testimonials and success stories – and why. (Beta investment: $27/month for founding members)
Join the waitlist HERE so you can be the first to know when the doors open!
