Could histamine be behind your unexplained symptoms?
Many of us at some stage in our lives experience troubling symptoms for which there is apparently no explanation.
Now a growing number of doctors and scientists believe histamine may be behind at least some of these undiagnosed issues.
They can range wildly from gut problems and diarrhea, to rashes and itchy skin, headaches, sinus problems, irregular periods, dizziness, anxiety and rapid heartbeat.
Histamine plays an important role in our immune system so in itself is not a problem, but when your body releases too much of it or is unable to break down excess histamine it creates a build-up and that in turn can create a wide range of symptoms which can be really debilitating.
Mast Cell Activation Syndrome & Histamine Intolerance: The Culprits Behind the Mayhem
There are two distinct but interlinked conditions thought to be behind some of the unexplained symptoms that can blight our lives.
They are Histamine Intolerance and Mast Cell Activation Syndrome (MCAS).
Histamine Intolerance
- Histamine intolerance occurs when your body has an imbalance between the amount of histamine it takes in (primarily from food) or produces, and its ability to break it down. This leads to an excessive accumulation of histamine in the body.
- The primary cause is often a deficiency or reduced activity of the enzymes responsible for breaking down histamine, mainly diamine oxidase (DAO). Genetic factors, certain medications, gut dysbiosis, and conditions that damage the intestinal lining can contribute to this enzyme deficiency.
- Symptoms including upset stomach, headaches, stuffy nose, and rashes, are typically triggered by consuming high-histamine foods including aged cheeses, fermented products, some fish, cured meats, alcohol) or foods that cause histamine release or block DAO activity including chocolate and tomatoes.
Mast Cell Activation Syndrome (MCAS)
- MCAS is a more complex immunological condition where mast cells, which are immune cells found throughout the body, become overly sensitive and release excessive amounts of histamine and other inflammatory mediators.
- In MCAS, the mast cells themselves are dysfunctional making them easily triggered and hyper-reactive.
- MCAS can be triggered by a wide variety of factors beyond just food, including stress, temperature changes (heat, cold), medications, infections, exercise, odors/fragrances, insect bites/stings, and hormonal fluctuations.
- The syndrome can cause a broad and severe range of symptoms affecting multiple body systems, often mimicking severe allergic reactions or even anaphylaxis. Symptoms can include:
- Skin: Flushing, hives, itching, swelling, dermatographism.
- Gastrointestinal: Abdominal pain, diarrhea, nausea, vomiting, acid reflux.
- Cardiovascular: Blood pressure changes (low or high), rapid heart rate, fainting, dizziness.
- Respiratory: Wheezing, shortness of breath, nasal congestion, coughing.
- Neurological/Psychiatric: Headaches, brain fog, fatigue, anxiety, depression, sleep disturbances.
- Other: Chronic pain, muscle weakness, sensitivity to light/sound. Symptoms often come in episodes or “flares” and can be severe and life-threatening in some cases.
How are these conditions treated?
Histamine Intolerance treatment primarily focuses on reducing histamine intake and improving its breakdown. MCAS treatment focuses on stabilizing mast cells and blocking the wide array of inflammatory mediators they release.
If you are experiencing histamine intolerance or MCAS symptoms you should seek advice from an experienced healthcare provider who may suggest some of the following approaches.
Treating Histamine Intolerance
- Low-Histamine Diet:
- The cornerstone of HIT treatment is often a strict low-histamine elimination diet for a period to see if symptoms improve. This involves avoiding foods naturally high in histamine and those that trigger histamine release or block DAO enzyme activity.
- After the elimination phase, some doctors recommend foods are slowly and systematically reintroduced to identify individual tolerance levels.
- Higher histamine foods: Aged cheeses, fermented foods (sauerkraut, kombucha, yogurt, kefir), cured meats, processed meats, some fish (tuna, mackerel, sardines), alcohol (especially red wine, beer), spinach, tomatoes, eggplant/aubergine, strawberries, citrus fruits, chocolate, certain food additives.
- Foods generally well-tolerated: Fresh meats, fresh fish, most fresh vegetables (except those listed above), fresh fruits (except those listed above), gluten-free grains, fresh dairy substitutes, cooking oils.
- Important Note: A low-histamine diet can be restrictive and potentially lead to nutritional deficiencies. It should ideally be followed under the guidance of a healthcare professional or a dietitian experienced in HIT.
- DAO Enzyme Supplements:
- Taking oral diamine oxidase (DAO) enzyme supplements before meals can help break down histamine from food in the gut, reducing the histamine load. This directly addresses the enzyme deficiency.
- Antihistamines:
- H1-antihistamines (e.g., cetirizine, loratadine, fexofenadine): These block histamine’s effects on H1 receptors, reducing allergy-like symptoms such as itching, hives, and flushing.
- H2-antihistamines (e.g., famotidine): These block histamine’s effects on H2 receptors in the gut, primarily addressing gastrointestinal symptoms.
- Helpful:
- Ensuring adequate intake of nutrients essential for DAO activity, such as Vitamin C, Vitamin B6, Copper, and Zinc.
- Hormonal Balance: In some women, hormonal fluctuations (e.g., estrogen dominance) can impact histamine levels, and addressing these imbalances may be part of the treatment.
Treating Mast Cell Activation Syndrome (MCAS)
MCAS treatment is more complex and aims to stabilize dysfunctional mast cells, prevent their activation, and block the effects of the various mediators they release (not just histamine). It often involves a multi-pronged approach.
- Trigger Avoidance:
- Identifying and avoiding individual triggers (which can be broad and include foods, chemicals, scents, temperature changes, stress, exercise, medications, infections) is crucial for preventing flares. Keeping a detailed symptom and exposure diary is often very helpful.
- A low-histamine diet can be beneficial for many MCAS patients as histamine is a major mediator released by mast cells, but it’s not the only dietary consideration, and some MCAS patients may not react significantly to dietary histamine if other mediators are the main triggers.
- Mast Cell Stabilizers:
- Some medications can help prevent mast cells from being overactive.
- Cromolyn Sodium: This is a mainstay for MCAS, particularly for gastrointestinal symptoms. It works locally in the gut to stabilize mast cells.
- Ketotifen: It acts as both a mast cell stabilizer and an H1-antihistamine.
- Quercetin: A natural flavonoid, often taken as a supplement, that has mast cell stabilizing and antihistamine properties. It’s often used as an adjunct to other treatments. Vitamins D and C may also have supportive roles in mast cell function.
- Other Medications:
- Since mast cells release multiple mediators, blocking various receptors is often necessary through the use of antihistamines and other medications.
The Expert View
Dr Tina Peers built her expertise in histamine intolerance the hard way and she will share the heartbreaking story of how her daughter suffered terribly before they were able to finally identify the root of the problem and start to treat it.
Having begun her career as a general practitioner, Dr Peers later specialized in menopause and remains the clinical lead at The Menopause Consultancy.
She has built significant expertise in treating histamine issues as well as long covid, and now practices integrative medicine where she works with patients to find the root cause of conditions rather than simply treating symptoms.
She explains why the conditions are so under-recognized.
“This was first put together by someone linking all of the different systems and inflammation being the common theme between all of the systems. So whether it’s bronchitis or sinusitis or it’s IBS-type symptoms with ulcerative colitis or all the inflammations, eczema, psoriasis, rosacea, all these inflamed conditions.
“Somebody pulled that together in the 80s, and it was given a name of histamine intolerance and mast cell activation in the 90s. And it was in 2007 that case studies were published in medical literature, so a long time had gone without it being flagged to the medical profession in particular, and to the patients very importantly.
“Most doctors didn’t know anything about it and had never heard of it and yet they are seeing it constantly in their clinics, in their GP practices, in their gastroenterology clinics, in their neurology clinics, in their headache clinics, dermatology, etc. They weren’t aware of it so they couldn’t join up the dots. And it is a little bit like a dot to dot. And once you start joining up the dots, you get a very clear picture of what’s going on everywhere in the person and then how to help them, which is the most important thing.
“If you can understand what’s going on, then you can start to make some improvements to their health.”
While Dr Peers says pharmaceutical interventions can be necessary at first, she believes lifestyle changes are key to tackling symptoms long term, reducing your intake of high-histamine foods, for females, potentially adjusting estrogen levels in discussion with your prescriber, using mast cell supporting supplements like DAO, quercetin, vitamin C and vitamin D, and she recommends drinking dandelion tea as another natural way of stabilizing mast cells.
She added: “Obviously we want to encourage people to have as natural an approach as possible.
“Look at having a low histamine diet, some vitamins and minerals to support your system. Natural antihistamines like high dose vitamin C and quercetin, which is a mast cell stabilizer. Drinking dandelion tea, a couple of cups a day. It has quercetin in it as has nettle tea.
“These are anti-inflammatory natural things that you can use, and that can help to reduce histamine.
“It’s important that people, if they believe that they have a history that sounds suggestive of MCAS and histamine issues, that they seek a clinic that understands these issues.”
