Histamine intolerance is a condition that is generally managed with diet and lifestyle changes. The most well-known of these may be the low histamine diet, in which foods that are naturally high in histamines and those that may contribute to histamine release are avoided.
We know that what we eat affects our histamine levels. But there are a number of other, often surprising factors that can contribute to increased histamine levels and our overall load.
What Causes Histamine Overload?
Before we get into the more specific factors that can increase histamine levels, it’s important to understand the different groupings that contribute to our overall histamine load.
Sources of histamine can be generally broken down into two categories: endogenous (internal) and exogenous (external).
Exogenous, or external, sources of histamine are essentially food sources. When we eat something that contains high levels of histamine (including fermented or aged foods and processed foods), this contributes to our overall histamine load.
This is especially true if DAO activity or levels are low, as DAO is the enzyme that is responsible for breaking down dietary histamine.
Endogenous, or internal, sources can be a bit more complicated. Mast cells, a type of white blood cell, release histamine as part of our normal immune system response. However, in some cases, mast cells are activated too frequently, releasing unnecessary amounts of histamine.
In managing histamine intolerance, it’s worthwhile considering all of the different kinds of factors that may be increasing levels through these different pathways. For example, what may cause mast cells to become overactive, DAO activity to decrease, or histamine-producing gut bacteria to proliferate?
7 Surprising Factors That Can Increase Histamine Levels
Symptoms of histamine intolerance often fluctuate with the seasons, or when traveling to different places. In some cases, this may be due to the varying presence of allergens. For some people, excessive heat can also act as a trigger.
When body temperature rises, it can trigger the activation of mast cells in the skin and muscles, leading to histamine release (2).
How to deal: Depending on where you live, hot weather for at least part of the year may be unavoidable. Try to avoid too much direct sun on hotter days, and stay cool indoors with the help of fans, breathable bedding, and a splash of cold water on your face as needed. You may also want to limit excessively hot or long showers and baths.
2. Strenuous exercise
For some people, physical activity, especially high intensity aerobic exercise, may lead to symptoms like itchiness and redness or dizziness and weakness. Some have described feeling like they’re “allergic” to exercise.
Research has largely attributed this phenomenon to the muscular inflammation that occurs during exercise, provoking a mast cell response and histamine release (3, 4). Exercise also leads to an increase in body temperature, which may exacerbate the issue.
The release of histamine from mast cells has also been associated with delayed muscle soreness after exercise (5).
How to deal: When it comes to managing exercise and histamine, it’s all about balance. Although exercise may produce an inflammatory response in the short-term, the long term effects are actually anti-inflammatory, and exercise is an important component of a healthy lifestyle (6, 7).
Start by focusing on more moderate, gentle forms of exercise like yoga, walking, or light strength training, monitoring how you feel before introducing anything more vigorous. Make sure to allow a generous amount of recovery time between exercise sessions. You may also want to avoid eating right before exercising, as this can contribute to further histamine release.
When we experience stress, our mast cells receive signals that lead them to activate and release histamine. Research has actually found that stress is the most common trigger of Mast Cell Activation Syndrome and mastocytosis (8).
How to deal: Stress management is an important component of any histamine intolerance protocol. Psychological stress can’t be completely eliminated, but it’s essential to introduce or maintain practices that can help you to regulate it. Stress management practices may include mindfulness meditation, yoga, spending time in nature, or taking time to sit and read.
If you find yourself struggling to manage stress in your daily life, you may want to consider working with a Cognitive Behavioral Therapy (CBT) practitioner to learn practical techniques and strategies for coping with life’s various challenges.
The use of some medications may contribute to increased histamine levels, often by blocking DAO (the enzyme that breaks down dietary histamine).
Medications that may inhibit DAO include some Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) which include Advil and Aleve, antibiotics, antidepressants, antacids, diuretics, and immune modulators (11). Some of these medications, including NSAIDs and antibiotics, may also contribute to inflammation and dysbiosis within the gut, which may exacerbate the problem (12, 13).
Some antihistamine medications can also lead to increased histamine levels by inhibiting DAO. While it may seem confusing that antihistamines would increase histamine levels, it’s important to understand that these medications generally work by blocking histamine receptor sites rather than actually decreasing levels of circulating histamine. So, while they may be effective for acute situations (like an allergic reaction), they are not necessarily helpful when it comes to lowering your overall histamine load.
How to deal: If you regularly take any medications that may inhibit DAO, consider speaking with your practitioner about alternative options. You may also want to try to limit your use of over-the-counter NSAIDs and antihistamines like Advil or Benadryl. Make sure to consult with your doctor before making any changes to your medication regimen.
5. Your menstrual cycle
If you are someone who menstruates, you may find that your histamine symptoms worsen before your period. The female sex hormone estrogen, which naturally increases when you are ovulating and just before your period, has been shown to increase mast cell activation and histamine levels (14).
How to deal: The factors that contribute to increased histamine levels before your period are natural. The best thing you can do is to keep track of your cycle so that you know when this time is coming, and be especially aware of additional histamine triggers around this time, keeping your overall histamine load in mind.
If your symptoms are severe during ovulation, and/or if you experience painful periods, you may also want to consider speaking with a practitioner about testing for any hormonal dysregulation that could be playing a role.
6. Gut imbalances
Gut conditions can lead to or contribute to histamine intolerance in a number of ways. First of all, different kinds of gut bacteria can either produce histamine or help to degrade it (17). Gut dysbiosis (an imbalance between helpful and harmful bacteria within the gut microbiome) can lead to excessive levels of histamine-producing bacteria.
Gastrointestinal disorders including SIBO, leaky gut, gluten intolerance, dysbiosis, and IBS can also influence levels of DAO.
Finally, the gut is a major component of the immune system and contains a high volume of mast cells, which are influenced by the gut bacteria that live among them.
How to deal: Gut issues are often at the root of histamine problems, whether or not we’re aware of them. There are a number of functional medicine tests, including the GI-MAP test, that can help to break down what’s going on in your gut so that you can focus on healing.
7. Vitamin or mineral deficiencies
The body relies on adequate levels of certain vitamins and minerals in order to produce DAO (18). These include magnesium, vitamin B6, vitamin C (which is also a natural antihistamine), and zinc.
Sometimes, especially when following a restricted diet due to sensitivities, levels of these vitamins and minerals may be too low, and can contribute to histamine intolerance.
How to deal: Speak to your practitioner about testing for levels of these and other vitamins and minerals. If low, supplementation may be recommended.
The Bottom Line
Living with histamine intolerance is all about managing your overall histamine load. The more we can understand about our triggers and factors that are contributing to this load, the better equipped we are to manage the condition and reduce the likelihood or severity of symptoms.
It’s not a matter of being afraid of food, exercise, or stress, but of being aware and informed.
For more personalized guidance on histamine intolerance, Mast Cell Activation Syndrome, or a related condition, request a consultation with Dr. Gannage.