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For many years, I suffered from thyroid issues that were driven by gut problems, heavy metals, and viruses. If you read my first book, The 30-Day Thyroid Reset Plan, you may know a little about my story. But what most people don’t know is that one of the most significant issues—in addition to my thyroid symptoms and general ill health—was mast cell activation syndrome (MCAS) and, therefore, histamine intolerance. Mast cells (white blood cells) are responsible for releasing histamine. This isn’t a bad thing unless your body isn’t equipped to break down histamine properly or you’re producing more histamine than your body can handle, which happens to be the case with MCAS.
It wasn’t until I started learning about histamine intolerance as a functional medicine practitioner that I finally began to piece together the puzzle. I realized that my symptoms and food sensitivities were being driven by histamine intolerance. I created the plan outlined here. Most of the symptoms I suffered are gone, and I now live a pretty normal life day-to-day.
What Is Histamine?
Histamine is a chemical your body makes that plays a number of different roles, but its main function is to get rid of allergens. When histamine is released, it causes inflammation to alert the body of potential pathogens. This is a natural part of the body’s immune response, and for those who don’t suffer histamine intolerance, enzymes later break down the histamine to prevent it from building up and causing ill health.
Histamine is also involved in digestion through stomach acid as well as the central nervous system, where it works as a neurotransmitter, delivering messages between the body and the brain.
When Histamine Becomes a Problem
Histamine can become an issue when it builds up. This can occur when the body is suffering from certain metabolic disturbances, such as a defect in enzyme-producing genes, that make it difficult to break down and metabolize histamine in the proper way. When this happens, histamine can affect the brain, gut, lungs, and cardiovascular system, causing a number of unwanted symptoms, including:
The 4-Phase Histamine Reset Plan
Phase 1: Eliminate
If you have histamine intolerance or suspect that you do, the first step is to
remove high-histamine and inflammatory foods from your diet for 1–3 months. It’s very important to keep a food diary as a way to help determine which foods are triggering immediate symptoms.
This doesn’t mean you’ll have to keep these foods out of your diet forever. The diet may be a temporary measure until your histamine levels stabilize and you start to feel better. However, you may find that you have to keep some foods out of your diet forever.
Foods that are problematic for those with histamine intolerance include:
- Aged Cheese: including goat cheese
- Citrus Fruits: oranges, grapefruit, pomelo (exception: you may be able to tolerate lemons and limes)
- Canned & Cured Meats: bacon, pepperoni, salami, lunch meat, canned meats, hot dogs
- Dried Fruits: apricots, dates, figs, prunes, raisins
- Fermented Foods: kefir, Kombucha, sauerkraut, soy sauce, vinegar (gluten-free white distilled vinegar and apple cider vinegar are lower in histamine and may be okay)
- Fermented Alcohol: beer, champagne, wine especially
- Legumes: beans, lentils, peanuts, soy
- Nuts: cashews and walnuts
- Processed Foods: all types, preservatives are high in histamine
- Soured Foods: buttermilk, sour cream, sour milk, etc.
- Smoked fish & these Species of Fish: anchovies, mackerel, mahi-mahi, sardines, tuna, fish sauce
- Veggies: avocados, eggplant, and spinach
- Vinegar-Containing Foods: olives and pickles
These foods aren’t high in histamine, but they cause histamine release in the body.
These foods block DAO, the enzyme needed to break down histamine.
• Black tea
• Energy drinks
• Green tea
• Mate tea
Phase 2: Support the Liver
Liver support is critical—too much histamine can lead to liver-enzyme changes, harming the organ. And liver dysfunction can lead to histamine intolerance. It’s therefore important to give your liver some love. Try:
Epsom Salt Baths
These are a natural way to support the liver through detoxification, and they can also be very relaxing (reducing stress is a big part of controlling histamine intolerance). The magnesium sulfate in Epsom salts is what helps remove built-up toxins from the body.
Castor Oil Packs
I recommend castor oil packs, which you can place over your liver to support liver function. Heritage Store makes a starter kit.
These are a fabulous tool for anyone with histamine intolerance. They can provide detoxification benefits just like moderate exercise. Infrared saunas are particularly helpful in releasing toxic contaminants such as mercury and lead. Enjoy two or three times per week.
Supplements to support the liver include milk thistle and NAC.
Phase 3: Go Deeper
Heal your gut: Certain bacteria in the gut can produce histamine, leading to a buildup of histamine in the body while also impairing DAO function. And digestive enzymes are extremely important for those suffering with histamine intolerance, as most people with this condition tend to need help breaking down food properly.
If you take a probiotic for gut health, know that some strains of beneficial bacteria can actually raise histamine levels because they are fermented. With limited research on histamine intolerance and probiotics, the following strains have been found to be acceptable for those with histamine intolerance, and they may also be able to lower inflammation: B. bifidum, B. infantis, B. longum, B. lactic, B. rhamnosus, L. plantarum, and L. salivarius.
Sooth your stress: Because stress is a big histamine trigger, supporting the
adrenal glands is essential to combating histamine intolerance symptoms and lowering inflammation. I highly recommend meditation and visualization. Meditation switches off the genes related to inflammation, while visualization can quickly change your mindset, lower stress when you are experiencing histamine-related symptoms, and aid the healing process.
Phase 4: Reintroduce
You can now reintroduce certain high-histamine foods into your diet. Try the food for three days and track any symptoms you experience. If you do experience symptoms, eliminate the food right away. You may never be able to eat certain high-histamine foods, even if your body is able to tolerate histamine better. Test each of the foods one by one and keep a very detailed food journal to identify what will and will not work for your body.
Having histamine intolerance can be overwhelming and confusing. However, there are a number of things you can do to feel better and get your histamine levels under control. I’d like to stress the importance of working with a functional medicine practitioner or taking part in my Histamine Intolerance Online Course (DrBeckyCampbell.com) to uncover all of your triggers and support your whole body, so that you can enjoy the absolute best outcome.
Here are examples of foods that you can eat freely on a low-histamine plan:
8 Common Causes of Histamine Intolerance
Mast Cell Activation Syndrome (MCAS)
In MCAS, a wide range of triggers, such as genetic predisposition, gut microbiome dysbiosis, and infections, cause mast cells to release inflammatory mediators and histamine. When mast cells are triggered, they can spill chemicals into your body, one of which is histamine, causing a wide range of symptoms. There are tests available for MCAS, as well as doctors who specialize in treating it.*
Gluten can be problematic for more than one reason. Apart from the fact that it is an inflammatory substance, gluten is especially harmful for those suffering from a thyroid condition, as the body can mistake gluten for healthy thyroid tissue and vice versa. Wheat, rye, barley, malt, durum, semolina, farina, farro, graham, and kamut are gluten-containing grains.
Leaky gut is a condition in which the barrier of the intestines becomes “leaky.” When foreign substances gain access to the bloodstream (via small holes that develop in the intestines), they can trigger an autoimmune reaction in the body and create inflammation, skin issues, fatigue, digestive complaints, food allergies, and histamine intolerance.
Microbial and fungal infections and histamine intolerance often go hand and hand. H. pylori, SIBO, Candida, and parasites are gut infections that have been linked to histamine intolerance. Mastic gum, methylmethionine sulfonium (vitamin U), and DGL have been used to successfully treat H. pylori.
Inflammatory Digestive Diseases
Inflammatory bowel diseases (IBD), which include Crohn’s disease and ulcerative colitis, are closely linked with issues relating to low DAO, due to the inflammatory effects they have on the body. Histamine levels can also be higher in the gut in IBD sufferers.
Having a deficiency in certain vitamins or minerals can lead to problems with low DAO. For example, copper and vitamin C help increase DAO function, and they can also be helpful in reducing histamine levels. So having a deficiency can lead to a decrease in DAO or poor DAO function. Vitamin B6 and zinc are also vital players in treating histamine intolerance.
Certain genetic mutations are often linked with histamine intolerance, particularly MTHFR and HNMT genes. MTHFR is needed to make the enzyme methylenetetrahydrofolate reductase, which plays a very important
role when it comes to methylation and removing toxins from the body. Histamine needs methylation in order to be processed and eliminated from the body.
NSAIDs, antidepressants, immune modulators, anti-arrhythmics, antihistamines, histamine blockers (Pepcid, Zantac, Tagamet), and aspirin can all lead to low DAO. You might be surprised to see antihistamines on the list—they can indeed lead to a depletion of DAO in the body, making histamine intolerance worse.
Article reprinted with permission from The 4-Phase Histamine Reset Plan by Dr. Becky Campbell (Page Street Publishing Co., 2019).