Histamine Intolerance: Symptoms, Root Causes & Natural Solutions for Relief

You've tried everything.

You're not crazy and you're not alone. You've eliminated gluten, dairy, maybe even gone full carnivore or AIP. You've seen multiple doctors who tell you your labs are "normal." Yet you're still dealing with mystery symptoms. Maybe it's the heart palpitations that come out of nowhere, the anxiety that spikes before your period, the skin that feels like it's on fire, or the gut issues that only show up during certain weeks of your cycle.

What if I told you that many of these seemingly random symptoms could be connected to one thing: histamine intolerance? And what if the solution isn't just about avoiding high-histamine foods, but about addressing the root causes...your hormones, gut health, nervous system, and more?

If you have PMDD, tune into this podcast episode to see if Histamine Intolerance could be behind your PMDD Symptoms.

If you've been told "it's just allergies", "it's all in your head," or what you're experiencing is "normal" keep reading. This might be the missing piece you've been looking for. Nothing in this blog post is medical advice. Please seek out your medical provider if symptoms are new or worsen.

What is Histamine?

Histamine is a crucial chemical in our immune system and overall health. When your immune system is triggered, mast cells (immune cells found throughout your body) release histamine along with other inflammatory compounds.

While histamine gets a bad rap for its role in allergic reactions, it actually plays many important roles in the body including regulating neurotransmitters, increasing stomach acid production, supporting the sleep-wake cycle, muscle contraction, ovulation, and libido.

The problem isn't histamine itself—it's when you have too much of it.

What is Histamine Intolerance (HIT)?

Think of histamine like a bucket. Once your histamine bucket fills up and starts to overflow, you experience what's called "histamine intolerance" or histamine excess.

Histamine intolerance doesn't mean your body is sensitive to histamine. It means you have an excess of histamine from either:

• Too much production and release of histamine OR
• Inability to break it down properly due to impairment in the enzymes needed (DAO and HNMT enzymes)

Symptoms of Histamine Excess

Histamine intolerance can be difficult to identify because symptoms are vague and varied:

• Food sensitivities
• Heart palpitations
• PMDD and period pain
• POTS and exercise intolerance
• Gut issues in the second half of your menstrual cycle
• Shortness of breath and chronic congestion
• Year-round allergies
• Skin issues: rashes, hives, flushing, feeling like skin is on fire, eczema, rosacea
• Pelvic pain and bladder issues like interstitial cystitis
• Diarrhea and migraines
• Severe anxiety and panic attacks
• "Period flu"
  
  

What Fills Up the Histamine Bucket?

Environmental & Lifestyle Factors

• Environmental toxins and mold
• Stress and trauma
• High histamine foods (dairy, red wine, beer, smoked meats, fermented foods)
• Medications that reduce DAO (naproxen, antihistamines, antidepressants)

Hormonal Imbalances/ Hormones

• Low progesterone
• Estrogen dominance
• Progestins in hormonal birth control

Poor Gut Health

• Leaky gut
• Gut infections: SIBO, H. pylori, candida, parasites
• Irritable Bowel Disease
• Certain probiotics that are histamine producers (see below)

Other Factors

• Nutrient deficiencies (vitamin C, B6, copper, magnesium, zinc)
• Genetic mutations (HNMT, MTHFR)
• Endocrine disruptors (fragrances, BPA, parabens, phthalates, pesticides)
  
  

What is the difference between Histamine Intolerance + MCAS? 

The Menstrual Cycle, Estrogen & Histamine Connection

This is a crucial piece many women miss. Estrogen and histamine create a vicious cycle:

Estrogen increases histamine: Mast cells have estrogen receptors, and when estrogen binds to these receptors, more histamine is released. Estrogen also down-regulates DAO, the enzyme that breaks down histamine.

Histamine increases estrogen: More histamine can ramp up estrogen production, perpetuating the cycle.

The two times estrogen is highest in your cycle are right before ovulation and in the luteal phase—notice how symptoms might worsen during these times? Your hormones are playing a role in this.

Progesterone is protective: It stabilizes mast cells and up-regulates DAO, helping to counteract histamine issues. This is why low progesterone (not just high estrogen) is a major trigger for histamine intolerance.

Histamine & the Nervous System

Stress is an often-overlooked trigger for histamine issues. And I don't just mean a stressful job—being type A, go-go-go, under-eating, skipping breakfast, and lots of intensive exercise can all impact your nervous system and histamine.

The longer your sympathetic nervous system is activated, the more mast cells are activated, increasing histamine release. Remember, histamine acts as a neurotransmitter in the brain, affecting GABA, dopamine, and serotonin. Too much histamine can trigger anxiety, panic attacks, and depressive feelings.

Histamine & the Liver

A congested liver from years of toxin exposure, poor diet, blood sugar imbalances, stored stress, toxic heavy metals, viruses, bacteria, pharmaceuticals, and excess hormones can increase inflammation and trigger histamine issues.

Pathogens create waste products that become toxins driving inflammation and histamine. High histamine can increase liver enzymes and bilirubin, while high liver enzymes can increase histamine—another vicious cycle.

Histamine & Gut Health

Your gut microbiome plays a huge role in regulating histamine levels since a large chunk of our immune system resides in the small intestine.

Poor gut health or "leaky gut" decreases DAO enzyme levels (DAO is made in the gut lining). Pathogens like H. pylori, SIBO, candida, and parasites can increase histamine. Gut dysbiosis can also increase beta-glucuronidase, an enzyme that unbinds toxins and excess hormones like estrogen that should be eliminated.

Probiotic warning: Certain probiotics are histamine producers and can worsen histamine intolerance: Lactobacillus casei, Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus delbrueckii, Lactobacillus helveticus, Bacillus licheniformis.

Here's Exactly Where I'd Start To Reduce and Even Resolve Histamine Intolerance Symptoms.

This is my 5 step RESTORE framework that I utilize with all my 1:1 clients that helps them get relief from painful periods, endo symptoms, bloat, fatigue, food sensitivities, etc.

1. Blood Sugar Balance

Stable blood sugar reduces stress hormones, boosts progesterone, and reduces estrogen.

• Eat within 1 hour of waking
• Minimum 3 balanced meals daily (protein, fats, carbs/fiber at every meal)
• Aim for 100g protein minimum and 25-30g of fiber (start slow)
• Exercise to build muscle and improve insulin sensitivity
• Support your liver (it's a glucose reservoir)

2. Nervous System Support

Balance your blood sugar FIRST—no amount of meditation or cold plunging will help if your stress hormones are dysregulated from blood sugar issues.

Then:

• Slow down
• Get enough sleep
• Address mineral imbalances
• Set boundaries
• Practice somatic/vagus nerve work: body scanning, humming, deep breathing
• Consider EMDR therapy, journaling, shadow work
• Work through trauma and stop suppressing emotions

3. Gut Health

• Ensure daily bowel movements (toxins and excess estrogen won't be eliminated without regular poops)
• Address fiber, stress, and minerals (potassium and magnesium)
• Treat infections—consider GI map stool testing if you have endo or autoimmunity
• Reduce ultra-processed foods and increase anti-inflammatory foods
• Address food sensitivities (consider eliminating dairy and/or gluten temporarily)
• Use histamine-reducing probiotics: Bifidobacterium infantis, longum, bifidum, breve; Lactobacillus plantarum, rhamnosus, gasseri, salivarius; Saccharomyces boulardii
• Consider mold and parasite testing

4. Minerals

Minerals support your nervous system, gut motility, thyroid, hormone balance, and immune system. Calcium, magnesium, sodium, and potassium are the four macro minerals, and imbalances can drive histamine issues.

Copper is an important cofactor for DAO, but too much can drive estrogen. Low zinc/high copper can signal low progesterone.

• Magnesium glycinate for mood and sleep (topical magnesium is also great)
• Ensure electrolyte intake, especially if you exercise and sweat
• Use high-quality salts (Celtic salt, Redmond's Real Salt) with food and drinks
• Avoid depleting minerals by drinking plain water all day
• Consider HTMA testing to learn your specific imbalances

5. Environment & Detoxification

Support liver detoxification with key nutrients:

Phase 1: B vitamins, folate, vitamins A, D, C, E, calcium, glutathione Phase 2: Magnesium, omega-3s, quercetin, high-quality animal protein

Practical strategies:

• Eat cruciferous veggies (natural DIM): broccoli, cabbage, cauliflower
• Include: eggs, beef liver, wild salmon, leafy greens, citrus, berries, nuts, avocado, beets
• Quit or significantly reduce alcohol (impacts liver detox, causes gut inflammation, blocks DAO)
• Ditch fragrances and xenoestrogen chemicals in cosmetics, toiletries, laundry detergents
• Warm lemon water in the morning to stimulate bile flow
• Castor oil packs (45 min-1 hr)—great for those very sensitive to histamine
• Epsom salt baths or foot baths (start with 1/2 cup)
• Dandelion tea, sauna/infrared sauna
• Bitter foods (arugula) or digestive bitters

Low Histamine Diet (Temporary)

Reducing dietary histamine may help if you're very sensitive. Common high-histamine foods to be mindful of: dairy, red wine, beer, fermented foods, smoked meats, canned fish, tomatoes.

Remember: This diet is NOT meant to be followed long-term as it's very restrictive. The goal is to reduce histamine, not completely eliminate it from your life.

Yes, there are over the counter medications like Allegra, Zyrtec + Pepcid that can help alleviate symptoms. But there are also some herbs/ supplements that can also help reduce symptoms.

Helpful Supplements/ Herbs

• Nettle Leaf: reduces histamine + has a lot of vitamins + minerals. (get my nettle infusion recipe here)
• Vitamin C: Helps clear histamine
• Vitamin B6: Supports the DAO enzyme
• Quercetin: Reduces histamine release from mast cells (stinging nettle tea is high in this)
• DAO enzyme: Improves histamine clearance
• Kidney Beef organs: contains DAO
• D-Hist: Blend of herbs to reduce histamine
• Seeking Health Histamine Digest: Provides DAO to reduce reactions to meals
• Sulforaphane: Hormone-safe way to support estrogen detoxification
• Bioidentical progesterone therapy: Talk to your provider or try Pro-Adapt
• Herbs: NAC or milk thistle for liver support

Histamine intolerance is complex and multifaceted, but by addressing blood sugar, nervous system health, gut health, minerals, and environmental toxins, you can support your body's ability to manage histamine naturally. Remember, the goal isn't perfection—it's progress and finding what works for your unique body.

If you've tried a lot of things and still not seeing relief, it may be time to dig deeper. There are a few tests I love to utilize with my histamine intolerance clients that can help us uncover what's fueling your symptoms.

Here are the 3 main tests I use with my clients:

GI MAP:

• allows us to rule out pathogens
• potential gluten sensitivity
• assess absorption
• inflammation + rule out IBD

HTMA:

• assesses for heavy metals/poor liver congestion
• assesses for mineral imbalances that may be contributing to hormonal issues, poor adrenal output, poor gut health, etc

DUTCH:

• assesses hormones like estrogen + progesterone + their metabolites
• detoxification of estrogen
• stress hormones/circadian pattern
• methylation
• neurotransmitters

There are ways for us to test what's contributing to your symptoms, because it's NOT just allergies and it's definitely not just food. We also don't want to just slap a bandaid (like an antihistamine) on this issues without getting curious about what's causing them in the first place.

This is where people like me come in.

If you're sick of MCAS + HIT symptoms having so much of an impact on your life, this is exactly what I help my clients with inside my world. If you'd like deeper support so you can finally get relief, book a free consult call using the link below or send me a DM on instagram!