Unraveling the Allergy-Gut Connection: A Journey to Histamine Balance

Welcome to The Perfect Stool: Understanding and Healing the Gut Microbiome. This is your host, Lindsey Parsons, and today I'm going to be talking about allergies and the gut. This includes regular seasonal allergies, dust mites, pollen, pets, et cetera, as well as histamine dysregulation and histamine intolerance related to foods you eat and gut conditions like SIBO. But before we get to that, if If you haven't yet followed or subscribed to the show, be sure to do so. And if you want to get transcripts of the podcast, pop over to my website, HighDesertHealthCoaching.com, and sign up for my newsletter. You'll also get my free ebooklet called Finding Your Root Cause Through Stool and Organic Acids Testing when you sign up. And if you haven't yet done my quiz on which stool test would help you get to your root cause, you can find a link in the show notes and take that. Now on to the show. So I'm going to start with what allergies are and what causes allergic reactions in the body. Allergies are immune system reactions to substances that are typically harmless to most people but trigger an exaggerated response in those who are allergic. The immune system plays a crucial role in protecting the body from harmful invaders such as viruses and bacteria. However, in the case of allergies, it can mistakenly identify allergens like pollen, dust mites, pet dander, or certain foods as threats. When someone with allergies encounters these allergens, their immune system releases chemicals like histamines and cytokines from their mast cells, which are cells found in the skin and mucous-lined surfaces of the— including the digestive tract— which are intended to ward off the perceived threat. These chemicals cause common allergy symptoms such as sneezing, itching, swelling, and congestion. Essentially, allergies are the result of the immune system's overzealous response to substances it incorrectly perceives as dangerous. And I'm sure you're familiar with the over-the-counter cures for allergies— antihistamines like Claritin, Zyrtec, and Benadryl— which help quell the histamine response. But these antihistamines are like putting a Band-Aid on the issue by blocking histamine receptors, but they don't actually do anything about the histamine levels themselves. So they're great for comfort, but they're not a long-term fix and have unwanted side effects like drowsiness and lower stomach acid levels, which will impact your protein digestion and can lead to a higher stomach and intestinal pH, which, as I will explain later, is counterproductive. So let's dig a bit more into histamine. First of all, it's not just the chemical our bodies produce when our immune system goes into battle mode, but it's also involved in a lot of other biochemical processes, including regulating our digestion, helping us to build stomach acid, and serving as a neurotransmitter that regulates other neurotransmitters like serotonin. Histamine is also involved in helping wake us up as part of our sleep cycle, and it's involved in our circulatory system, menstrual cycle, and in regulating inflammation, meaning not just creating inflammation but also regulating it. So it's really an incredibly important chemical that our body produces, and we can't just try to block all of it because of that. In a typical scenario, our body both produces and breaks down histamine. This is crucial to maintain balance. However, sometimes the balance goes awry, and this breakdown process relies on two major enzymes: diamine oxidase, or DAO, and histamine N-methyltransferase, or HNMT. When we lack these enzymes, histamine accumulates and we end up with more histamine than our body can handle. This excess histamine can lead to a range of problems. This may look like skin rashes, eczema, hives, sensitivity to cold or heat, pounding headaches, fatigue, brain fog, constant nasal drip, asthma, heightened anxiety, disrupted sleep patterns, digestive issues like heartburn, bloating, or diarrhea, and food intolerances. And of course, sneezing and watery eyes and those sort of typical allergy symptoms. Essentially, when there's an abundance of histamine circulating in our body, it binds to histamine receptors all around our body, causing disturbances and intensifying these symptoms everywhere. There are two terms that describe this allergic situation. One is histamine dysregulation, where we produce too much histamine and suffer the consequences of excess histamine wreaking havoc in our system. The other is histamine intolerance. This latter term relates to the body's ability to break down histamine from ingested foods. And I imagine many of you may not be aware that histamine is also present in many of the foods we eat. Histamines are found particularly in aged or fermented foods like sauerkraut, wine, or aged meats or cheeses, and foods that have gone bad or have been stored for a long time. And even some seemingly innocent foods like avocado, spinach, or tomatoes have natural levels of histamine. Then there are foods that cause the release of histamine, like citrus, bananas, dairy products, chocolate, pineapple, nuts, strawberries, food additives, shellfish, and artificial dyes and preservatives. Some of those also have high histamine levels on top of causing the release of histamine. When you consume foods that naturally contain histamine or histamine-releasing foods, your gut usually deploys the enzyme D— DAO to break down the histamine. However, in histamine intolerance, there's often a deficiency of DAO, or it doesn't function optimally, resulting in an inability to effectively break down the histamine from these foods. As a result, histamine from the ingested foods gets absorbed into the bloodstream leading to increased systemic histamine levels. This can cause symptoms like headaches, hives, digestive problems, and more, specifically triggered by the histamine-containing foods you eat. In essence, the main distinction lies in the source of the excess histamine. Histamine dysregulation or— originates from the body's overproduction of histamine, while histamine intolerance is primarily linked to the inability to process histamine from foods due to DAO deficiencies or dysfunction. Both can lead to a variety of symptoms, but they have different underlying mechanisms. Now, what you may not realize is the way that SIBO, or small intestine bacterial overgrowth, can lead to histamine-related issues. First, when we have an overabundance of bacteria in our digestive tract, it tends to generate inflammation. Certain bacteria, the gram-negative ones, produce substances known as lipopolysaccharides, which can trigger the mast cells to release histamine within the digestive system. So when there's a substantial inflammation due to bacterial overgrowth, it results in increased utilization of DAO. As a result, we might deplete our DAO reserves, making it insufficient to handle the histamine from our diet. That's one way the bacterial overgrowth can contribute. Secondly, recent research points to certain types of bacteria commonly associated with SIBO being histamine producers. In a study in which the stool was examined to find the connection between urinary histamine and bacteria in IBS patients, It was found first that IBS patients with high urine histamine had a gut microbiome that produced significantly more histamine, and second, that Klebsiella aerogenes was the primary histamine producer, producing 100 times more histamine than other bacteria. Other previous research has also suggested Morganella morganii as another potential high gut histamine producer, and Klebsiella, incidentally, is known as one of the primary overgrown bacteria in SIBO. Which is why many SIBO sufferers also have histamine intolerance, because an overgrowth of these histamine-producing bacteria in our gut depletes our DAO reserves and interferes with our histamine tolerance. So it's a double whammy effect from both inflammation from gram-negative Klebsiella and excess histamine produced by bacteria in the context of bacterial overgrowth. So some people dealing with terrible allergies are not just getting them from environmental triggers but may also be experiencing histamine intolerance related to diet and not realize it. In addition to SIBO in particular, research has revealed a compelling link between gut health and allergies, with multiple studies showing that individuals with allergies often exhibit alterations in their gut microbiome composition characterized by a reduced diversity of beneficial bacteria. This imbalance, referred to as dysbiosis, can lead to a weakened gut barrier, allowing allergens and toxins to pass through more easily, aka a leaky gut. Furthermore, research has suggested that certain gut bacteria such as specific strains of Bifidobacterium and Lactobacillus, may play a protective role against allergies by regulating the immune system and promoting tolerance to allergens. Conversely, disruptions in the gut microbiome's balance have been associated with an increased risk of developing allergies, including food allergies, hay fever, and asthma. Now let's talk about how to modulate the gut in order to reduce histamines. As noted above, an abundance of Klebsiella aerogenes, which produces histamines, can be part of the problem. And researchers have discovered that Klebsiella aerogenes is most prolific in producing histamine when the pH of the gut is around 7.0, but histamine production nearly ceases when the pH drops below 6.0 or rises above 8.0. This finding is significant because the colon's pH typically ranges from 5.5 to 7.5, with lower pH values associated with better colon health. So modifying the colon's pH to increase its acidity, meaning lowering the pH, could be a strategy to reduce histamine production by K. aerogenes. And let me credit Lucy Maling for these insights into histamine intolerance and colon pH and many of the suggested interventions before I go on. So how do we lower colon pH? Well, specific bacterial strains like Bifidobacteria and Lactobacilli increase lactic acid levels, playing a role in colon pH. Researchers have observed that in humanized mice with a microbiota from IBS patients who had high urine histamine levels, lactic acid levels were notably lower. Not surprisingly, they also found reduced levels of lactic acid-producing bacteria, including lactobacilli. Further investigation revealed that certain lactobacilli could modulate histamine production by K. aerogenes, likely through the production of lactic acid. This suggests that specific lactobacilli strains may contribute to regulating histamine production by K. aerogenes. While much of the discussion has centered on the colon, it's also essential to consider the presence of Klebsiella species in the small intestine, which of course would be the site of SIBO. Studies have indicated that Klebsiella species may be more prevalent in the duodenum, the upper portion of the small intestine, in individuals with gastrointestinal symptoms. This presence in the small intestine can potentially disrupt the overall microbial community. Furthermore, it suggested that some Klebsiella species found in the gut may originate from the oral cavity, indicating that saliva could act as a reservoir for transmitting Klebsiella to the gut, where they may flourish if the gut environment is conducive. Hence the importance of good dental hygiene. In portions of the small intestine with lower acidity, such as the ileum, which can have pH levels as high as 7.4 to 7.8, histamine production by K. aerogenes may be supported. In summary, K. aerogenes produces histamine, and its production is influenced by pH levels, while lactic acid and specific Lactobacilli and Bifidobacteria strains can impact this process. Additionally, Klebsiella's presence in the small intestine may also contribute to histamine production, particularly in less acidic regions. Now, if your allergy symptoms are worse after eating certain foods, or you have lots of gut symptoms in addition to allergic symptoms, or at the same time as them, you may have a histamine intolerance problem. So how can you bring down your gut pH and try to reduce your populations of inflammatory bacteria? Here are some potential interventions. Now the trick here is that you may not be able to tolerate these interventions while populations of Klebsiella or other histamine-producing bacteria are high, so it may be necessary to use antimicrobial herbs first to bring down the bacteria. But after that, you can start interventions for changing the environment in your gut and bringing down your gut pH. One first easy step is by eating lots of lacto-fermented foods that have high amounts of lactobacilli, which will produce lactic acid and reduce the pH in your gut. My next episode will actually be about fermenting foods, so stay tuned for that. Second, you can take probiotics with lactobacilli. One strain in particular, Lactobacillus plantarum 299v, has been shown in clinical trials for IBS to be better tolerated by histamine-sensitive individuals. You can find it in the Jarrow Formulas Ideal Bowel Support Probiotic and Metagenetics Ultraflora Intensive Care or Hyperbiotics Pro-IBS Support, all of which are available in my FullScript dispensary and linked in the show notes. And there are also a number of probiotics that are designed for breaking down histamine and have no histamine-producing strains, which many do. These include Seeking Health's Probiota HistamineX and Vitanica's Florasymmetry. And I've also provided links for those. Third, you can include vinegar with or before your meals, which has been shown in animal models to reduce colonic pH. Usually, you know, people have apple cider vinegar, a tablespoon or two in water before a meal. Other potentially beneficial interventions for people with histamine intolerance include butyrate or its preferred supplement form, tributyrin, which may help to promote colonic acidity and suppress mast cell activation. And of course, I have to plug my supplement Tributyrin Max here, but keep in mind that tributyrin will slow colon motility. So if you're constipated, I pick a lower dose butyrate supplement than mine and only use one every few days. But if your stool is loose, a higher dose one like Tributyrin Max is a good choice. I'd start with 1 with a meal and titrate up to as many as 1 to 2 per meal until your stool is solid with a clean wipe, decreasing it when and if you get constipated. If you have any signs or possible contributing factors to low stomach acid, like low pancreatic enzymes, H. pylori overgrowth, low chloride levels on a blood test, specifically under 100 mmol/L, abnormally high or low serum protein and serum globulin levels, especially in the presence of relatively normal liver enzymes, which are the ALT and the AST, low phosphorus levels, high BUN levels of 20 mg/dL or more, or B12 or iron deficiencies, or acid reflux— all of those potential signs of low stomach acid— supplementation with betaine HCl, which is just supplementary stomach acid, will reduce the pH of the stomach and small intestine. And then doing things to reduce colon transit time and increase colon motility, especially if you're constipated, will also help with a lower colon pH. My go-tos for that are vitamin C and magnesium citrate. For vitamin C, I usually recommend the Perk Sea Guard powder, a quarter teaspoon, 3 times a day, and increase from there as needed. And then the Natural Vitality Calm Magnesium, which comes in plain or a variety of flavors, which is magnesium carbonate and turns into magnesium citrate when you mix it in water. And this helps with motility. I'll link to the orange one, but you can find all the flavors and the plain in my full script dispensary at a discount. And I recommend starting with a half teaspoon before bed and increasing by a half teaspoon every 2 days until you hit 2 teaspoons or even more you know, is needed to get the colon moving. If this isn't enough to get things moving, you may have a bad case of IMO, or intestinal methanogen overgrowth, and may need some antimicrobial interventions too. Then of course there's eating a low histamine diet, and I'll link to Dr. Jocker's low histamine food plan in the show notes. But ideally that's a temporary fix until you get the gut issues under control. And then finally, time-restricted eating will help, meaning only eating when it's light out, because Klebsiella aeruginosa proliferates more rapidly in the presence of melatonin, which comes out at night. And I actually have a former client whose symptoms pointed very strongly towards histamine intolerance, who had a terrible nighttime itching. And she reached out to me to tell me that when she implemented a 17-hour nightly fast, stopping eating after 4 or 5 PM, her itching went away. Then of course there are other supplements that help stabilize or modulate mast cells and may decrease your symptoms. Quercetin is one of the best known. Taking 500 milligrams a half hour before you eat may be helpful if your symptoms point to histamine intolerance. And I've linked to one possible quercetin, or taking one 500mg capsule a day on an ongoing basis if your allergies do not seem food-related. Curcumin and silymarin are also mast cell stabilizers, and curcumin is a great general anti-inflammatory. So I'll link to a few products that have both of those substances in them in the show notes. These types of products with silymarin tend to be geared towards liver support. So if you're concerned you have liver issues like fatty liver, high fasting glucose, or hemoglobin A1C or skin issues or drink a lot of alcohol, then these types of supplements might be a good double duty in helping support your liver. And then there are actual DAO supplements to, to provide the enzyme to break down the histamine. And although I've heard mixed results about their efficacy from other practitioners, I do have clients who swear by them. Two examples are Designs for Health Histogest DAO and Seeking Health's Histamine Digest. Now, beyond the advice for people with gut-related histamine issues or histamine intolerance, I wanna highlight the lifestyle interventions that will help people people with regular seasonal allergies and other types of allergies that don't seem to be related to the gut. But keeping in mind that with 70% of our immune system found in our gut, decreasing systemic inflammation via the gut is still relevant. First, try to increase your dietary diversity by consuming a diverse range of fiber-rich foods such as fruits, vegetables, whole grains, and legumes. And I'll especially highlight the importance of legumes, meaning beans, lentils, split peas, hummus, etc. In providing adequate dietary fiber and supporting a diverse gut microbiome. I recommend getting 1/4 to 1/2 cup of these high-fiber foods, foods a day. And on top of that, I particularly recommend the following foods for their immune-balancing and histamine-managing properties: parsley, coriander, raw red onion, broccoli, nettle, and tulsi teas, and fresh ginger and turmeric. These natural options can help balance your immune response and manage histamine. Second, incorporate probiotic-rich foods like yogurt, kefir, sauerkraut, and kimchi into your diet. These foods contain live probiotic cultures that can support a balanced microbiome. Third, include healthy prebiotics in your diets from foods like garlic, onions, leeks, and asparagus, which also serve as nourishment for beneficial gut bacteria. Four, limit processed foods and sugary foods, which often contain additives and preservatives that can negatively affect gut health and which will feed pathogenic organisms in the gut. Fifth, make sure you stay hydrated. This is important to keep your system moving and not have stagnation and constipation, not to mention supporting overall digestion and ensuring a suitable environment for gut bacteria to thrive. Half of your body weight in ounces, if you measure your weight in pounds, is recommended as a minimum. Sixth, try to manage your stress. I've seen so many clients whose health declined in response to a major stressful period in their life. You can do this by first trying to change the way that you perceive stress. Sometimes work can be fast-paced and challenging, and our lives, and if you perceive it that way, then your body will not necessarily ramp up the cortisol commensurate with the stress response. But if you perceive it as stressful and negative, it will. Or if you set up unreasonable expectations of the people around you, and I'm speaking from experience here, thinking things like, my children should never say no to me or talk back to me, then you'll no doubt have a higher stress response than if you have more reasonable expectations like Sometimes kids do so about their parents, and my job is to guide them gently. And then you can also pick out a stress reduction technique you like, such as meditation, yoga, prayer, breathwork, or Epsom salt baths, which have the added benefit of giving you magnesium. Try to get in at least 10 to 15 minutes of a relaxation technique a day. And finally, if you're in a toxic relationship or have toxic people in your life, start the process of considering when and how to remove yourself from toxic people enlisting the help of a therapist or friends as necessary. Seventh, avoid the overuse of antibiotics, especially for upper respiratory infections that are usually viral in nature. If your doctor has given you antibiotics in the past, you're more likely to request and expect them, and your doctor is more likely to give them to you. But if anything, the best stance is to challenge a doctor who wants to prescribe you antibiotics unless it's confirmed that you have a bacterial infection, and then making sure that you get the most narrow-spectrum antibiotic you can and for the shortest duration recommended. 8, engage in regular exercise, which has been linked to a more diverse and balanced gut microbiome. And finally, prioritize getting adequate, meaning 7 to 9 hours of quality sleep, which supports immune function and contributes to overall wellbeing. Now, there are additional supplements that may support gut health for people with regular allergies, which in turn can have a positive impact on the allergies. Here are some supplements associated with potential benefits for allergies through their influence on gut health. I mentioned probiotics earlier for people with histamine intolerance, but let me add that if you have seasonal type allergies, you may want to look at a spore-based probiotic. One of the most researched ones is called Enterogermina, which comes out of Italy but is very reasonably priced for a 20-vial course on Amazon. In studies, it was shown to reduce nasal congestion and the need for antihistamines. Spore-based probiotics have also been shown to reduce postprandial, meaning after a meal, lipopolysaccharide levels, which is one cause of inflammation. Research also suggests that the most common probiotic strains, Lactobacillus and Bifidobacterium, may reduce allergy symptoms by modulating the immune response. A very well-researched combo probiotic is Seed Symbiotic, which has some strains in it that were particularly researched for helping with allergies. If you can't get enough prebiotic fiber in your diet from fruits and vegetables, ideally from 5 servings a day, you may want to try a prebiotic supplement to provide the fiber and nutrients that beneficial bacteria need to thrive. One good option is Pure Encapsulations Poly Prebiotic Powder. Then if you're not eating 2 servings of fatty fish like salmon, sardines, or anchovies a week, then I'd recommend an omega-3 fatty acid supplement. Either fish oil or algae oil, if you're vegan or vegetarian, have anti-inflammatory properties and may help reduce allergic inflammation and support overall gut and immune system health. My favorites are Nordic Naturals Pro Omega 2000, which I like because you get 1,000 mg of EPA and DHA in one, which is a sufficient dose for most people. And if you have high cholesterol issues too, you may wanna take two of those. And of course, pick grass-fed or pasture-raised eggs, beef, lamb, and dairy if you eat it for the higher omega-3 content. If you're a vegan or vegetarian, you can use an algae oil like Nordic Naturals Algae Omega, but you may need to take more of them to get to 1,000 mg of EPA and DHA and may need even more than that if you're not getting it from your diet. And the one of the most important substances for immune health is vitamin D. Adequate vitamin D levels are important for a balanced immune response and may help reduce the risk of allergies. I have yet to see a single client who achieved optimal vitamin D status without supplementing. I suggest you get your vitamin D tested and shoot for an optimal range of 60 to 80 ng per ml. If you aren't there, most people I find need about 3,000 to 5,000 IU a day to get there and stay there. Which I always recommend to combine with vitamin K2, preferably in the MK-4 form. I like the drops because you can adjust your dose as you test and retest your levels, which is good to do about every 6 months. I only know of one D3-K2 drop with K2 in the MK-4 form, which is the Adapt Naturals ones, and I link that in the show notes. Then you may have specific other vitamin and mineral deficiencies that are necessary for creating the DAO enzyme. The most common ones are vitamin B6, which is best gotten in a complete methylated B complex, and I'll include a good one from Priority One that's got a reasonable amount of all the B vitamins in it in the show notes. Although if you've had any identified B vitamin deficiencies or have issues like anxiety or depression, you may want to select a B complex with higher levels of related B vitamins. I should also note that I don't think I've ever seen a test from a client who had sufficient levels of all the B vitamins. I'm not sure if this is a poor diet issue or a gut health issue or a soil depletion issue, but I recommend a B complex to pretty much everyone I work with. Then the other vitamins and minerals for making DAO are vitamin D, as previously mentioned, vitamin C, and magnesium. They're all essential for breaking down histamine and managing histamine levels via DAO. And finally, black seed oil, derived from cumin seeds, has also been found in research on rats and humans to be effective in decreasing markers of allergic inflammation, nasal mucosal congestion, nasal itching, runny nose, and sneezing attacks. It also has antifungal properties So if you're dealing with Candida as well as allergies, it's a good choice. I prefer the liquid as you can get a lot more in 1 teaspoon of it than you can put in a capsule, and I'll put a couple good ones in the show notes. And if none of this helps you, I should also note that if you have a mold history or history of mold in your home or workplace, or if you've had Lyme disease or Bartonella or potential risk, they can also cause these types of allergy symptoms and what's called mast cell activation syndrome. Bartonella can also give a sense of buzzing or vibrations in the body. So if you're having those kind of symptoms, you may want to do further testing to see if those are possible issues, either in the home, in your body, or in both. Well, I hope this was helpful in giving you some ideas for dealing with your allergies. As always, if you want some professional help, I work with clients with gut and all over chronic health issues. So if you've been through the conventional medicine roller coaster and you're struggling still with bloating, gas, burping, nausea, constipation, diarrhea, soft stool, acid reflux, IBS, IBD, SIBO, Candida overgrowth, fatigue, migraines, and of course allergies, and you wanna get to the bottom of it, that's what I help my clients with. You're welcome to set up a free 30-minute breakthrough session if you think you might like to sign up for a 3 or 5 session package, or I offer individual consultations as well. You can find links for those in the show notes. If you'd like to support the show, you can make a regular donation on Patreon or buy vetted high-quality supplements from my full script dispensary, or gimme a 5-star review on Apple Podcasts. To reach out to me in other ways, I have a Gut Healing Facebook group for asking questions, or I'm on Instagram, Pinterest, and Twitter, and now TikTok. Links for all those are in the show notes or on my website, HighDesertHealthCoaching.com. Thanks for listening. Here's wishing you all the perfect stool.