What Is Histamine Intolerance—and Could It Be Affecting You?
Understanding the Symptoms, Triggers, and clinical connections Behind Histamine Intolerance
If your body reacts unpredictably to certain foods…
If you feel bloated, itchy, anxious, or inflamed—and nothing you’ve tried is helping…
If you’ve been told your symptoms are “just allergies,” but deep down you know there’s more to the story—
You’re not alone. And you’re not imagining it.
Histamine intolerance is often overlooked—but it can be the common thread behind symptoms that seem completely unrelated.
What Is Histamine?
Histamine is a natural chemical your body makes. It plays essential roles in:
Immune response
Brain signaling
Digestion (as part of stomach acid)
It’s not the presence of histamine that’s the problem—it’s when there’s too much and your body can’t keep up with breaking it down.
What Causes Histamine Intolerance?
While histamine is naturally produced in the body (and found in food), it needs to be broken down—primarily by the DAO enzyme.
Histamine intolerance happens when:
You’re producing or consuming more histamine than your body can clear
DAO activity is low or impaired
There’s an underlying issue triggering excess histamine release
The “Histamine BUcket”
Your body has a threshold for how much histamine it can handle at one time. That threshold gets pushed when histamine levels rise from multiple sources—such as food, gut imbalances, or toxin exposure.
If the total load exceeds your body’s ability to break it down—primarily through the DAO enzyme—symptoms begin to show up. This is often referred to as the “histamine bucket” effect: once your bucket overflows, your body reacts, and that’s when you get symptoms like flushing, bloating, anxiety, or hives.
What Are the Symptoms of Histamine Intolerance?
Histamine intolerance can affect everything from digestion to mood to skin. When seemingly unrelated symptoms show up across different areas of the body, it’s easy to miss the connection.
Common symptoms include:
Flushing, redness, or heat in the face or chest
Itching or tingling of the skin, lips, or tongue
Bloating, nausea, or digestive upset after meals
Racing heart or lightheadedness
Fatigue or brain fog that sets in after eating
Sinus congestion, sneezing, or headaches
Anxiety or restlessness—especially after food or wine
Hives, eczema, or rashes
Shortness of breath or asthma-like symptoms
Symptoms that worsen around your cycle or shift throughout the month
Root Causes
To truly lower your histamine burden, we need to understand why histamine is building up in your body—and what might be interfering with your ability to break it down.
Common root causes of histamine intolerance include:
Gut dysbiosis
Small intestinal bacterial overgrowth (SIBO)
Leaky gut
Mold or toxin exposure
Estrogen dominance or hormone imbalance
Nutrient deficiencies (like B vitamins, copper, or iron)
Medications that interfere with DAO
Genetic variations
Chronic stress and elevated cortisol
The Mold + Histamine Connection
Mold toxins—also called mycotoxins—are harmful compounds released by certain toxic molds commonly found in water-damaged buildings. These toxins activate mast cells—immune cells that release histamine (and many other inflammatory mediators)—and contribute to chronic inflammation, oxidative stress, and increased reactivity in the body. At the same time, mold toxins can interfere with the enzymes responsible for breaking down histamine. This creates a double impact: more histamine being released, and less being cleared. For individuals with histamine intolerance or Mast Cell Activation Syndrome (MCAS), mold toxins can be a powerful and often overlooked trigger that keeps the body stuck in a reactive, inflamed state.
The Hormone-Histamine Connection
Estrogen and histamine are closely linked.
Estrogen increases histamine release
Estrogen lowers DAO levels (the enzyme you need to break it down)
Progesterone helps calm things down by stabilizing mast cells and inhibiting histamine release—but many women are low in it.
If histamine issues flare or shift during certain times of your cycle, these hormonal influences may be part of the reason why.
The Gut-Histamine Connection
Gut dysbiosis can contribute to histamine intolerance—certain types of bacteria produce histamine, and others activate mast cells.
If there’s an overgrowth of the kinds of bacteria that trigger histamine production or activate mast cells, your body could be producing way more histamine than it can handle.
This is why gut repair is foundational. Without it, food avoidance can only go so far.
The SIBO–Histamine Connection
Histamine intolerance is especially common in people with SIBO. When bacterial overgrowth affects the small intestine, it can damage the gut lining—reducing the body’s ability to make DAO, the enzyme that breaks down histamine. At the same time, certain bacteria involved in SIBO can actually produce histamine themselves. Add in low-grade inflammation and mast cells becoming more reactive in the small intestine, and it’s easy to see how SIBO can significantly raise your histamine load.
Where Food Fits In
One of the quickest ways to reduce symptoms is by lowering your histamine intake through food.
Identifying and lowering your histamine load through food can provide relief while we address the root causes. In my practice, I have clients cut these foods for just a few weeks before they start reintroducing them to identify triggers.
Histamine-Liberating Foods
(Can trigger histamine release)
Eggs
Pork
Seafood
Avocado
Citrus
Kiwi
Raspberries
Nuts and seeds
Allspice, cardamom, cinnamon, cloves, nutmeg
Sesame oil
High-Histamine Foods
Bell pepper
Spicy peppers (chili, cayenne, sauces)
Eggplant
Olives
Spinach
Tomato
Banana
Bone broth
Coffee
Fermented sauces (soy, fish, tamari, coconut aminos)
Fermented vegetables (sauerkraut, kimchi, pickles)
Tomato sauce, ketchup, salsa
Mustard
Vinegars
Aged or seasoned meats (ham, bacon, sausage, smoked meats)
Butter, ghee
Yogurt and other dairy
Chocolate and cacao
DAO-Blocking Substances
Some compounds can interfere with the DAO enzyme and reduce histamine clearance:
Alcohol
Black tea and green tea
Energy drinks
Certain medications
Note: Always consult your provider before making any changes to prescribed medications.
How I Approach Histamine Intolerance in My Practice
Step 1: Reduce the Histamine Load
We start by lowering histamine levels through food—focusing on high-histamine triggers and, when appropriate, bringing in supportive histamine-lowering or histamine-digestive nutrients.
Step 2: Work on Gut-Related Histamine Issues
We address what’s happening in your gut—like SIBO, dysbiosis, leaky gut, or inflammation—because when things go awry in the gut, it can both trigger excess histamine and reduce your body’s ability to break it down.
Step 3: Address Other Root Causes
We address other root causes that may be impairing histamine breakdown or triggering excess release.
The Bottom Line
Histamine intolerance is often a sign that something deeper is elevating your body’s histamine levels or disrupting your ability to clear histamine.
The solution isn’t just food avoidance. It’s identifying the root causes, supporting your body’s ability to process histamine, and bringing foods back in when your body is ready.
There is a path forward—and it starts by understanding what your body is trying to tell you.
References
Jochum C. Histamine Intolerance: Symptoms, Diagnosis, and Beyond. Nutrients. 2024 Apr 19;16(8):1219. doi: 10.3390/nu16081219. PMID: 38674909.
Kritas SK, Gallenga CE, D’Ovidio C, Ronconi G, Caraffa A, Toniato E, Lauritano D, Conti P. Impact of mold on mast cell-cytokine immune response. J Biol Regul Homeost Agents. 2018 Jul-Aug;32(4):763-768. PMID: 30043558.
Vasiadi M, Kempuraj D, Boucher W, Kalogeromitros D, Theoharides TC. Progesterone inhibits mast cell secretion. Int J Immunopathol Pharmacol. 2006 Oct-Dec;19(4):787-94. doi: 10.1177/039463200601900408. PMID: 17166400.
Sánchez-Pérez S, Comas-Basté O, Duelo A, Veciana-Nogués MT, Berlanga M, Latorre-Moratalla ML, Vidal-Carou MC. Intestinal Dysbiosis in Patients with Histamine Intolerance. Nutrients. 2022 Apr 23;14(9):1774. doi: 10.3390/nu14091774. PMID: 35565742.