Histamine Intolerance

Mast cells are involved in innate and adaptive immune responses. They are highly present throughout the body. Mast cells release histamine, a neurotransmitter, a chemical messenger that sends messages between nerves. It does this through histamine receptors in the nose, mouth, Central Nervous System (CNS), circulatory system, sensory nerves, lungs, heart, gastrointestinal smooth muscle, adrenal medulla, immune cells, bladder muscle, and feet. In the brain, histamine is produced in the Posterior Hypothalamus, which keeps your body in a constant state of homeostasis (balance).

Mast cells are closely related to white blood cells and are triggered during the threat of allergy, inflammation, infection, or autoimmune disorders. They release histamine and heparin. Basophils and eosinophils (other white blood cells) also release histamines to respond to foreign pathogens. Heparin, by the way, is also an anticoagulant.

When too many mast cells are activated, irritation occurs. Symptoms include itching, rash, sneezing, runny nose, hives, and throat swelling. Chronic histamine imbalance can cause constipation and diarrhea (or alternating), migraine, fatigue, brain fog, moodiness, low blood pressure, nausea, weight gain, and inflammation. The release of histamines also leads to delayed muscle soreness, which is typical in Fibromyalgia Syndrome. 

Histamine intolerance is caused by the body producing too much histamine or eating too many histamine-releasing foods (or both). Certain gut bacteria can also produce histamine. The release of histamine occurs as a response to help fight inflammation. However, high histamine levels in the body can also cause inflammation. Why is this important to know? Inflammation is a major cause of disease. Just about anything the immune system feels it needs to attack will trigger the release of histamine. 

Ordinarily, histamine is regulated in the body by diamine oxidase (DAO) and histamine methyltransferase (HNMT) enzymes. Diamine oxidase breaks down histamine in the gut. A deficiency of DAO is often the cause of histamine intolerance. DAO decreases as we age. HNMT helps to degrade histamine. If deficient in this enzyme, you may also develop histamine intolerance.

Histamine is implicated in triggering the Herpes Simplex Virus, Fibromyalgia Syndrome, Chronic Fatigue Syndrome, and Irritable Bowel Syndrome. Moreover, the Herpes Simplex Virus causes Chronic Fatigue Syndrome, Interstitial Cystitis (bladder pain with no known cause), Fibromyalgia Syndrome, and Irritable Bowel Syndrome (IBS). Are you beginning to see the vicious cycle between histamine and overlapping conditions? Furthermore, histamine also triggers cortisol, the stress hormone, which also triggers histamine! By the way, you don't have to have a visible breakout to have the Herpes Simplex Virus pull the trigger. Many people live with the herpes virus and aren't aware of it.

Possible Causes of Histamine Overload

• Mast Cell Activation Syndrome
• Frequent infections, such as herpes viruses (such as HSV-1, HSV-2, Epstein-Barr Virus), or Lyme's
• Hormonal imbalances caused by high levels of cortisol, estrogen dominance, synthetic hormones (make mast cells work harder), and hormones derived from eating mass-produced animal products
• Eating too many high-histamine foods (see below)
• Consuming too many foods containing high levels of arginine triggers histamine.
• Autoimmunity
• Chondroitin deficiency
• Gut infections (Candida, SIBO) and Leaky Gut Syndrome
• Mold toxicity
• Lack of deep sleep (the body can't repair)
• Stress (the cortisol connection)
• Taking the supplement NAC (N-acetyl cysteine)
• DAO deficiency
• Low thyroid hormones (thyroid hormones help to regulate mast cells)
• Deficiencies in B (2, 5, 6, 12), folate (as methyl folate), and vitamin C will cause histamine levels to rise because, without these nutrients, you won't be able to produce histamine-blocking enzymes.

Histamine & Hormones

Because histamine, estrogen, and progesterone are closely related, women tend to have more histamine in their systems. Women still menstruating will often experience herpes breakouts around the time of their monthly cycle when estrogen levels soar and trigger histamine release. During menopause, estrogen dominance (when you have higher estrogen levels than progesterone) results in higher histamine levels, regardless of how little estrogen you have. Balancing these two can bring histamine levels down.

Foods High In Histamine or Histamine Liberating

Examples of Histamine Containing Foods (top offenders)

• Black and green tea
• Canned foods, especially meats
• Cured or smoked meat
• Processed foods
• Ready-made meals (TV dinners)
• Fermented foods
• Pickled foods, such as sauerkraut
• Aged cheese
• Mayonnaise
• Kombucha
• Alcohol (unless it's histamine-free)
• Apricots
• Raspberries are high in histamines but are full of quercetin, which lowers them
• Dried fruits
• Salty foods and snacks
• Spinach
• Tomatoes
• Tofu
• Soy sauce
• Mushrooms (except reishi)
• Sodas
• Fried foods
• Energy drinks
• Chocolate or cocoa
• Strawberries
• Kefir

Other Items That Liberate Histamine

• Iodine
• Magnesium citrate (possibly)
• Vitamin C (ascorbic acid), arginine, and citrulline cause histamine and herpes flare-ups. 
• B-complex (B-1 inhibits DAO)
• Taking the wrong probiotics (bulgarius, casei, delbrueckii, helvetica, streptococcus thermophilous)
• Foods high in oxalates

How to Inhibit Histamine

• Avoid foods that are histamine-rich or histamine-releasing.

• Taking an antihistamine interferes with the release of histamine and may be beneficial in the short term. From the non-drowsy group of antihistamines, you can take Allegra, Claritin, and Zyrtec Some report these antihistamines help ease Fibromyalgia Syndrome (FS) pain caused by histamine toxicity. Vistaril (Hydroxyzine) is sometimes prescribed for FS and Interstitial Cystitis. However, there can be adverse side effects to taking antihistamines. Antihistamine medications won't get rid of histamine. It will only block the receptors, which may seem acceptable, but when taken too often or in the long term, the body can start to ramp up histamine to compensate.

• In the natural world, quercetin is the go-to to reduce histamine flares. Quercetin is antibacterial, antiviral, and anti-inflammatory. Quercetin naturally reduces the amount of histamine in the body. For example, you can use it with D-mannose to ease the pain of Interstitial and Viral Cystitis. Taking quercetin (500 mg, two times daily for four weeks, no more than twelve) may help calm and heal the bladder lining. You can also take over-the-counter DAO enzymes and histamine blockers to see if they help, along with cutting high-histamine foods out of your diet for two weeks. Histamine may also play a role in Fibromyalgia Syndrome (FS). FS and bladder pain are often related. Specific prebiotics and probiotics encourage the release of histamine. Natural foods containing quercetin are cranberries, blueberries, and dark grapes. 

• Calcium deficiency keeps histamine from being held in check. Some people suffering from Interstitial Cystitis (bladder pain with no infection) have gone into complete remission after taking calcium. Take 500 mg daily of calcium citrate divided into three doses until your symptoms are relieved. You must take at least half to a third as much magnesium as they work together in the body. Then cut back to an amount appropriate for you. Take it with quercetin to knock out cystitis with a double whammy. 

• DAO (diamine oxidase) is an enzyme in the body, primarily in the gut, that helps reduce histamines. You can take DAO in supplement form (necessary in some cases). However, making appropriate changes in your diet is usually all that's needed to turn things around. If you decide to take DAO, you should have your histamine levels checked every so often to ensure you require it. It's essential to have balanced histamine levels (not too much and not too little). Your doctor can order a blood or urine test to detect your histamine levels.

• Zinc inhibits histamine. 

• Evening primrose oil and borage oil contain gamma linolenic acid (GLA), which lowers histamine levels. You might also run across information stating black current oil (black seed oil) has high levels of GLA. However, I don't suggest using it. Black seed oil also contains high arginine levels, which triggers herpes breakouts. 

• Prebiotics, probiotics, and dietary enzymes are essential for a healthy microbiome. However, some prebiotics and probiotics can encourage histamine intolerance. The types of probiotics that you want to avoid are lactobacillus (reuteri, helveticus, casei, and bulgaricus). Histamine-degrading probiotics are bifidobacterium (longum and infantis) and lactobacillus (rhamnosus, salivarius, and plantarum). Taking single strains is a good idea. Vitamin C also breaks down histamine in the body. Be sure to take enzymes and probiotics separately so they don't compete. 

• Taking fish oils is helpful. Just be aware that fish oils contain vitamin A and vitamin D. If you're also taking a multivitamin, check to be sure you're not overdoing either. 

Other Items That Inhibit Histamine

• Stinging nettles
• Slippery elm
• Amla (Indian gooseberry)
• Rose hips
• Cistus
• Medicinal mushrooms

What's Left To Eat?

There are several books available to help you manage a histamine-lowering diet. I wouldn't expect the authors to include these foods in an antihistamine regimen because they trigger histamines, but you never know. Sometimes, information could be more accurate.

• Fresh, organic meat and poultry (frozen is okay, but not canned, smoked, or cured)
• Eggs
• Fish, except mackerel, mahi mahi, tuna, anchovies, and sardines
• Fresh vegetables, except tomatoes, spinach, avocado, and eggplant), red onions.
• Reishi
• Green banana (unripe), plantain, mango, pear, watermelon, cantaloupe, grapes, kiwi, papaya, pineapple, berries (except strawberries)
• Dairy substitutes, such as coconut, hemp, rice, or almond milk and plain, organic yogurt
• Gluten-free grains (no yeast), such as rice (black rice stabilizes mast cells), quinoa, corn, millet, amaranth, oatmeal, potatoes, pumpkin, squash, and sweet potato
• Olive and coconut oils
• Basil, chamomile, cinnamon, clove, echinacea, oregano, fennel, fig, ginger, nutmeg, turmeric, thyme, stinging nettle, peppermint, rosemary, and oregano
• Herbal tea
• Chia seeds, flaxseed, and all-natural peanut butter
• Babies, toddlers, and those allergic to bees should never have honey. 

NOTE: If you struggle with Mast Cell Activation Disorder, Histamine Intolerance, or frequent allergy symptoms, I highly suggest an anti-inflammatory diet.