Your gut health is intricately connected to both seasonal allergies and food allergies.
The strength of this connection is likely because the largest density of immune cells in the body is in the small intestine.
Research shows that probiotics can significantly improve seasonal allergy symptoms.
Elimination diets can also help to improve allergy symptoms (including environmental allergies).
The connection between gut health and allergies, whether they’re food allergies or seasonal/environmental allergies, starts with the immune system. The immune system dictates whether the body needs to defend itself against certain foods or environmental substances.
When the immune system decides it needs to protect the body from a “harmless” substance, like lactose, pollen, or another environmental agent, we experience allergy symptoms. We may be exposed to some of these allergens in the air or through the sinuses, lungs, and skin. But we’re also exposed to many allergens through what we eat and drink. This is where the gut gets involved in allergic responses.
The largest density of immune cells in the body is in the small intestine — this is likely why the gastrointestinal tract has such a huge impact on the immune system and allergies.
Fortunately, this connection tells us where to target therapies for reducing allergy symptoms. Through strategies like elimination diets and probiotics, we have the opportunity to fortify the gut and the immune system to reduce allergy symptoms and regulate the immune response.
Defining Allergies, Sensitivities, and Intolerances
Allergies are an inappropriate and immediate immune response to foreign substances (known as antigens or allergens) that are typically harmless to the human body [1 Trusted SourcePubMedGo to source]. Allergic reactions usually occur in areas of the body that come into direct contact with an allergen . For example, foods can cause swelling in the mouth, pollen in the sinuses can cause a runny nose, etc.
Common allergic responses include:
Anaphylaxis: A sudden and severe allergic reaction that constricts the airway and therefore can be life-threatening [1 Trusted SourcePubMedGo to source]. It typically happens with foods, medications, insect stings, and allergen immunotherapies. For example, a peanut allergy may produce this response.
Allergic rhinitis (hay fever/seasonal allergies): Symptoms usually include runny nose, nasal congestion, sneezing, watery or itchy or red eyes, and nasal itching [3 Trusted SourcePubMedGo to source]
Food allergens: The most common problematic foods include milk, eggs, peanut, shellfish, wheat, and nuts [6 Trusted SourcePubMedGo to source].
House dust mites
Venom in insect stings and bites
Contact allergens such as metals or fragrance ingredients
Sensitivities, typically food sensitivities, also come from an immune response like allergies, but unlike allergies their symptoms are usually more vague and may even be delayed by hours. (Remember, allergic reactions are usually immediate and happen with direct contact to an antigen.)
Symptoms of sensitivities may include:
Joint or muscle pain
Common food sensitivities include gluten, dairy, soy, nightshade veggies like eggplant and tomatoes, and eggs. But a highly sensitized immune system can develop a sensitivity to just about any food, which may lead to more and more restrictive diets. It’s likely that food sensitivities develop from a leaky gut or inflammation from overgrowth of gut microbes, leading to immune system dysfunction.
Intolerances, unlike allergies and sensitivities, are not caused by an immune reaction. Instead, intolerances are caused by an insufficiency or defect in certain enzymes needed to break down a specific food or nutrient.
So lactose intolerance, for example, is caused by a lack of the enzymes needed to digest lactose. Histamine intoleranceis generally caused by a deficiency of the enzyme needed (diamine oxidase or DAO) to break down histamine in the body. A buildup of histamine can manifest as symptoms that feel like seasonal allergies, but without the allergen present.
Whether you’re dealing with allergies, sensitivities, or an intolerance, you can start to look at your gut health to identify how it may be contributing to your symptoms.
Food Allergies and Gut Health
Perhaps it’s unsurprising that there’s a connection between gut health and allergies to foods due to the significant presence of immune cells in the small intestine. Research shows that the following issues related to gut health may be connected to the development of allergies:
A key link to developing food allergies seems to be a decline in the health of the microbiome (our community of healthy gut bacteria in the colon). A literature review attempted to highlight the role of the microbiome in allergic diseases. The review found that infants with allergic diseases, including food allergy, atopic dermatitis (eczema), and asthma, have been shown to have reduced levels of healthyspecies of bacteria and elevated levels of pathogenic bacteria in the gut [24 Trusted SourcePubMedGo to source].
Another literature review that explored the role of gut microbiota in food allergies concluded that dysbiosis likely precedes food allergies, and the authors highlighted some research showing that improving gut health with probiotics may help to promote earlier resolution of food allergies in young children [26 Trusted SourcePubMedGo to source].
Seasonal Allergies and Gut Health
Making the connection between gut health and food allergies is a logical jump, but it turns out that gut health has a lot to do with seasonal and environmental allergies too.
Seasonal allergies also correlate closely with dysbiosis in both children and adults. Adults with seasonal allergies have also been shown to have lower levels of butyrate-producing bacteria [27 Trusted SourcePubMedGo to source] compared to healthy controls. Additionally, children with high levels of butyrate have been shown to have a reduced risk of developing allergies later in life [28 Trusted SourcePubMedGo to source].
Several GI disorders are associated with an increased risk of having seasonal allergies and other allergic conditions. IBS, functional dyspepsia, and constipation were associated with increased odds of having seasonal allergies, eczema, and asthma in one study [29 Trusted SourcePubMedGo to source].
Similarly, another study found that people with seasonal allergies and asthma were more likely to have GI symptoms compared to people with other chronic diseases and the general population [30 Trusted SourcePubMedGo to source]. Other gut conditions associated with seasonal allergies include inflammatory bowel disease [31 Trusted SourcePubMedGo to source], GERD, gastritis, peptic ulcers, IBS, functional GI disease, gastroenteritis, colitis, and/or constipation [32 Trusted SourcePubMedGo to source].
How to Use an Elimination Diet for Gut Health and Allergies
Whether you have obvious gut symptoms alongside your allergies or not, it may be helpful to do an elimination diet to identify any foods that may be triggering your symptoms. Research shows that people who go on elimination diets of various kinds (depending on their food triggers) have improved allergy symptoms.
Elimination diets also tend to be the best way to identify food sensitivities, such as non-celiac gluten sensitivity, since testing can be unreliable.
Here is the general process we recommend to patients for starting an elimination diet.
Step 1: Cut Out Processed Foods
This step eliminates a lot of added sugar, processed or trans fats and oils, and processed carbs, grains, and proteins. Replace processed foods with whole, fresh foods, making sure to meet your required nutrient intake.
For some people, this step alone is enough to resolve many of their symptoms. But if this isn’t enough, you can move on to step 2.
Step 2: Try a Paleo Diet
Paleo is the anti-inflammatory therapeutic diet we typically recommend to our patients when first starting to heal their digestion and lower systemic inflammation. Paleo prioritizes whole, fresh foods, including fruits and vegetables (lots of prebiotics), animal proteins, and some starchy vegetables. It eliminates dairy, grains (and therefore, gluten), processed foods, alcohol, soy, beans/legumes, most processed vegetable oils, and artificial sweeteners.
Some people can do a modified version of Paleo that includes some non-gluten grains like oats and rice, especially if they find they need extra carbs to maintain their energy levels. But some do very well on the no-grain version.
If your symptoms resolve on the Paleo diet after a few weeks, you can try adding certain foods back into your diet to see whether they trigger any symptoms. It’s important to reintroduce foods one at a time and monitor how you feel for a few days before moving on to another reintroduction.
But if Paleo doesn’t resolve your symptoms, you can move on to step 3.
Step 3: Try a More-Specific Elimination Diet Such as Low FODMAP
From the Paleo diet, you can try a more specialized diet like low FODMAP or a low histamine diet. Again, you’ll follow this diet for two to four weeks and then reintroduce foods one at a time to identify any trigger foods.
These diets do tend to be more difficult for people to follow, but the trick is to remember that it’s not forever, and you’re doing this to feel better. In the beginning, stick to a few basic meals and be willing to repeat meals often until you get a handle on what foods you can eat. Then you can expand into more meals and more food options. It also helps to batch prepare meals and stock your freezer for times when you’re tempted to reach for something outside of the diet.
If you don’t notice any improvements in two to three weeks, you don’t have to force yourself to stay on the diet. At this point, it may be helpful to consult with a healthcare provider on next steps.
Probiotics for Gut Health and Allergies
Probiotics (beneficial bacteria) are another proven therapy for allergy relief via gut health and microbiome support.
From our clinical perspective, we’ve seen probiotics help many patients handle histamine more effectively and reduce symptoms of histamine intolerance.
Reducing Dairy Allergy/Lactose Intolerance
Probiotics may also help improve lactose intolerance symptoms.
One systematic review and meta-analysis found that probiotics improved cow’s milk allergy in children compared to placebo [44 Trusted SourcePubMedGo to source]. An RCT found that probiotics combined with an elimination diet improved symptoms more than an elimination diet alone [45 Trusted SourcePubMedGo to source].
A review of nine RCTs investigated the effects of probiotics on lactose intolerance. A total of 304 subjects with lactose intolerance were included in the analysis. The results showed that probiotic use was associated with significant improvements in lactose intolerance symptoms and improved digestion (based on hydrogen breath test results) compared to control [46 Trusted SourcePubMedGo to source].
For lactose intolerance, the effects of probiotics may even last longer than enzyme supplements [47 Trusted SourcePubMedGo to source]. Plus, probiotics are helping to make your microbiota stronger as a whole, to improve overall digestion of everything you eat. It’s a win-win.
Should I Take Probiotics While on an Elimination Diet?
You can take probiotics while on an elimination diet, such as Paleo or low FODMAP (and this is typically what we recommend). However, if you’re just starting to change your diet, you’ll want to hold off on probiotics for at least a couple of weeks to see how your body responds to the dietary changes on its own.
The idea is that if we do too many things at once, we won’t know what changes are making a difference, or not making a difference. But, for example, if you’ve been on a Paleo diet for three weeks and you’ve seen some significant improvements in your allergy symptoms, but you want to know if you could feel even better with probiotics, adding in a high-quality probiotic is a logical next step.
Find Allergy Relief By Supporting Gut Health
If you suffer from seasonal allergies, food intolerances, or even histamine intolerance, fortifying your gut health might be your ticket to enjoyxing the turn into spring and summer this year. Finding the right therapeutic diet and diversifying your gut microbiome with probiotics are two strategies that can go a long way toward reducing allergy symptoms.
The Ruscio Institute has developed a range of high-quality formulations, including all-in-one triple therapy probiotics, to help our patients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you.
Steiner NC, Lorentz A. Probiotic potential of lactobacillus species in allergic rhinitis. Int Arch Allergy Immunol. 2021 Apr 21;182(9):807–18. DOI: 10.1159/000515352. PMID: 33882482. Trusted SourcePubMedGo to source
Deng Y, Misselwitz B, Dai N, Fox M. Lactose intolerance in adults: biological mechanism and dietary management. Nutrients. 2015 Sep 18;7(9):8020–35. DOI: 10.3390/nu7095380. PMID: 26393648. PMCID: PMC4586575. Trusted SourcePubMedGo to source
Mušič E, Korošec P, Šilar M, Adamič K, Košnik M, Rijavec M. Serum diamine oxidase activity as a diagnostic test for histamine intolerance. Wien Klin Wochenschr. 2013 May;125(9–10):239–43. DOI: 10.1007/s00508-013-0354-y. PMID: 23579881. Trusted SourcePubMedGo to source
Manzotti G, Breda D, Di Gioacchino M, Burastero SE. Serum diamine oxidase activity in patients with histamine intolerance. Int J Immunopathol Pharmacol. 2016 Mar;29(1):105–11. DOI: 10.1177/0394632015617170. PMID: 26574488. PMCID: PMC5806734. Trusted SourcePubMedGo to source
Sander GR, Cummins AG, Henshall T, Powell BC. Rapid disruption of intestinal barrier function by gliadin involves altered expression of apical junctional proteins. FEBS Lett. 2005 Aug 29;579(21):4851–5. DOI: 10.1016/j.febslet.2005.07.066. PMID: 16099460. Trusted SourcePubMedGo to source
Michielan A, D’Incà R. Intestinal permeability in inflammatory bowel disease: pathogenesis, clinical evaluation, and therapy of leaky gut. Mediators Inflamm. 2015 Oct 25;2015:628157. DOI: 10.1155/2015/628157. PMID: 26582965. PMCID: PMC4637104. Trusted SourcePubMedGo to source
Ventura MT, Polimeno L, Amoruso AC, Gatti F, Annoscia E, Marinaro M, et al. Intestinal permeability in patients with adverse reactions to food. Dig Liver Dis. 2006 Oct;38(10):732–6. DOI: 10.1016/j.dld.2006.06.012. PMID: 16880015. Trusted SourcePubMedGo to source
Mujagic Z, Ludidi S, Keszthelyi D, Hesselink MAM, Kruimel JW, Lenaerts K, et al. Small intestinal permeability is increased in diarrhoea predominant IBS, while alterations in gastroduodenal permeability in all IBS subtypes are largely attributable to confounders. Aliment Pharmacol Ther. 2014 Aug;40(3):288–97. DOI: 10.1111/apt.12829. PMID: 24943095. Trusted SourcePubMedGo to source
Moludi J, Maleki V, Jafari-Vayghyan H, Vaghef-Mehrabany E, Alizadeh M. Metabolic endotoxemia and cardiovascular disease: A systematic review about potential roles of prebiotics and probiotics. Clin Exp Pharmacol Physiol. 2020 Jun;47(6):927–39. DOI: 10.1111/1440-1681.13250. PMID: 31894861. Trusted SourcePubMedGo to source
Tursi A, Brandimarte G, Giorgetti G. High prevalence of small intestinal bacterial overgrowth in celiac patients with persistence of gastrointestinal symptoms after gluten withdrawal. Am J Gastroenterol. 2003 Apr;98(4):839–43. DOI: 10.1111/j.1572-0241.2003.07379.x. PMID: 12738465. Trusted SourcePubMedGo to source
Ghoshal UC, Shukla R, Ghoshal U. Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome: A Bridge between Functional Organic Dichotomy. Gut Liver. 2017 Mar 15;11(2):196–208. DOI: 10.5009/gnl16126. PMID: 28274108. PMCID: PMC5347643. Trusted SourcePubMedGo to source
Caminero A, Meisel M, Jabri B, Verdu EF. Mechanisms by which gut microorganisms influence food sensitivities. Nat Rev Gastroenterol Hepatol. 2019 Jan;16(1):7–18. DOI: 10.1038/s41575-018-0064-z. PMID: 30214038. PMCID: PMC6767923. Trusted SourcePubMedGo to source
Peroni DG, Nuzzi G, Trambusti I, Di Cicco ME, Comberiati P. Microbiome composition and its impact on the development of allergic diseases. Front Immunol. 2020 Apr 23;11:700. DOI: 10.3389/fimmu.2020.00700. PMID: 32391012. PMCID: PMC7191078. Trusted SourcePubMedGo to source
Shu S-A, Yuen AWT, Woo E, Chu K-H, Kwan H-S, Yang G-X, et al. Microbiota and food allergy. Clin Rev Allergy Immunol. 2019 Aug;57(1):83–97. DOI: 10.1007/s12016-018-8723-y. PMID: 30564985. Trusted SourcePubMedGo to source
Liu X, Tao J, Li J, Cao X, Li Y, Gao X, et al. Dysbiosis of fecal microbiota in allergic rhinitis patients. Am J Rhinol Allergy. 2020 Sep;34(5):650–60. DOI: 10.1177/1945892420920477. PMID: 32340468. Trusted SourcePubMedGo to source
Roduit C, Frei R, Ferstl R, Loeliger S, Westermann P, Rhyner C, et al. High levels of butyrate and propionate in early life are associated with protection against atopy. Allergy. 2019 Apr;74(4):799–809. DOI: 10.1111/all.13660. PMID: 30390309. Trusted SourcePubMedGo to source
Jones MP, Walker MM, Ford AC, Talley NJ. The overlap of atopy and functional gastrointestinal disorders among 23,471 patients in primary care. Aliment Pharmacol Ther. 2014 Aug;40(4):382–91. DOI: 10.1111/apt.12846. PMID: 24961872. Trusted SourcePubMedGo to source
Powell N, Huntley B, Beech T, Knight W, Knight H, Corrigan CJ. Increased prevalence of gastrointestinal symptoms in patients with allergic disease. Postgrad Med J. 2007 Mar;83(977):182–6. DOI: 10.1136/pgmj.2006.049585. PMID: 17344573. PMCID: PMC2599996. Trusted SourcePubMedGo to source
Soh H, Lee HJ, Han K, Park S, Hong SW, Moon JM, et al. Atopic Diseases Are Associated With Development of Inflammatory Bowel Diseases in Korea: A Nationwide Population-based Study. Clin Gastroenterol Hepatol. 2021 Oct;19(10):2072-2081.e6. DOI: 10.1016/j.cgh.2020.07.049. PMID: 32712393. Trusted SourcePubMedGo to source
Ho S-W, Lin C-P, Ku M-S. The impact of allergic rhinitis on gastrointestinal disorders among young adults. J Eval Clin Pract. 2020 Feb;26(1):242–7. DOI: 10.1111/jep.13108. PMID: 30773746. Trusted SourcePubMedGo to source
Güvenç IA, Muluk NB, Mutlu FŞ, Eşki E, Altıntoprak N, Oktemer T, et al. Do probiotics have a role in the treatment of allergic rhinitis? A comprehensive systematic review and meta-analysis. Am J Rhinol Allergy. 2016 Sep 1;30(5):157–75. DOI: 10.2500/ajra.2016.30.4354. PMID: 27442711. Trusted SourcePubMedGo to source
Tan-Lim CSC, Esteban-Ipac NAR, Recto MST, Castor MAR, Casis-Hao RJ, Nano ALM. Comparative effectiveness of probiotic strains on the prevention of pediatric atopic dermatitis: A systematic review and network meta-analysis. Pediatr Allergy Immunol. 2021 Aug;32(6):1255–70. DOI: 10.1111/pai.13514. PMID: 33811784. Trusted SourcePubMedGo to source
Farahmandi K, Mohr AE, McFarland LV. Effects of Probiotics on Allergic Rhinitis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. Am J Rhinol Allergy. 2022 Jan 31;19458924211073550. DOI: 10.1177/19458924211073550. PMID: 35099301. Trusted SourcePubMedGo to source
Costa DJ, Marteau P, Amouyal M, Poulsen LK, Hamelmann E, Cazaubiel M, et al. Efficacy and safety of the probiotic Lactobacillus paracasei LP-33 in allergic rhinitis: a double-blind, randomized, placebo-controlled trial (GA2LEN Study). Eur J Clin Nutr. 2014 May;68(5):602–7. DOI: 10.1038/ejcn.2014.13. PMID: 24569538. Trusted SourcePubMedGo to source
Dennis-Wall JC, Culpepper T, Nieves C, Rowe CC, Burns AM, Rusch CT, et al. Probiotics (Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and Bifidobacterium longum MM-2) improve rhinoconjunctivitis-specific quality of life in individuals with seasonal allergies: a double-blind, placebo-controlled, randomized trial. Am J Clin Nutr. 2017 Mar;105(3):758–67. DOI: 10.3945/ajcn.116.140012. PMID: 28228426. Trusted SourcePubMedGo to source
Anania C, Di Marino VP, Olivero F, De Canditiis D, Brindisi G, Iannilli F, et al. Treatment with a Probiotic Mixture Containing Bifidobacterium animalis Subsp. Lactis BB12 and Enterococcus faecium L3 for the Prevention of Allergic Rhinitis Symptoms in Children: A Randomized Controlled Trial. Nutrients. 2021 Apr 16;13(4). DOI: 10.3390/nu13041315. PMID: 33923532. PMCID: PMC8073063. Trusted SourcePubMedGo to source
Miraglia Del Giudice M, Indolfi C, Capasso M, Maiello N, Decimo F, Ciprandi G. Bifidobacterium mixture (B longum BB536, B infantis M-63, B breve M-16V) treatment in children with seasonal allergic rhinitis and intermittent asthma. Ital J Pediatr. 2017 Mar 7;43(1):25. DOI: 10.1186/s13052-017-0340-5. PMID: 28270216. PMCID: PMC5341466. Trusted SourcePubMedGo to source
Xiao JZ, Kondo S, Yanagisawa N, Takahashi N, Odamaki T, Iwabuchi N, et al. Effect of probiotic Bifidobacterium longum BB536 [corrected] in relieving clinical symptoms and modulating plasma cytokine levels of Japanese cedar pollinosis during the pollen season. A randomized double-blind, placebo-controlled trial. J Investig Allergol Clin Immunol. 2006;16(2):86–93. PMID: 16689181. Trusted SourcePubMedGo to source
Domingos-Lopes MFP, Stanton C, Ross RP, Silva CCG. Histamine and cholesterol lowering abilities of lactic acid bacteria isolated from artisanal Pico cheese. J Appl Microbiol. 2020 Dec;129(6):1428–40. DOI: 10.1111/jam.14733. PMID: 32500572. Trusted SourcePubMedGo to source
Kung H-F, Lee Y-C, Huang Y-L, Huang Y-R, Su Y-C, Tsai Y-H. Degradation of Histamine by Lactobacillus plantarum Isolated from Miso Products. J Food Prot. 2017 Oct;80(10):1682–8. DOI: 10.4315/0362-028X.JFP-17-135. PMID: 28885051. Trusted SourcePubMedGo to source
Dev S, Mizuguchi H, Das AK, Matsushita C, Maeyama K, Umehara H, et al. Suppression of histamine signaling by probiotic Lac-B: a possible mechanism of its anti-allergic effect. J Pharmacol Sci. 2008 Jun 5;107(2):159–66. DOI: 10.1254/jphs.08028fp. PMID: 18544899. Trusted SourcePubMedGo to source
Qamer S, Deshmukh M, Patole S. Probiotics for cow’s milk protein allergy: a systematic review of randomized controlled trials. Eur J Pediatr. 2019 Aug;178(8):1139–49. DOI: 10.1007/s00431-019-03397-6. PMID: 31230196. Trusted SourcePubMedGo to source
Cukrowska B, Ceregra A, Maciorkowska E, Surowska B, Zegadło-Mylik MA, Konopka E, et al. The Effectiveness of Probiotic Lactobacillus rhamnosus and Lactobacillus casei Strains in Children with Atopic Dermatitis and Cow’s Milk Protein Allergy: A Multicenter, Randomized, Double Blind, Placebo Controlled Study. Nutrients. 2021 Apr 1;13(4). DOI: 10.3390/nu13041169. PMID: 33916192. PMCID: PMC8066586. Trusted SourcePubMedGo to source
Leis R, de Castro M-J, de Lamas C, Picáns R, Couce ML. Effects of prebiotic and probiotic supplementation on lactase deficiency and lactose intolerance: A systematic review of controlled trials. Nutrients. 2020 May 20;12(5). DOI: 10.3390/nu12051487. PMID: 32443748. PMCID: PMC7284493. Trusted SourcePubMedGo to source
Almeida CC, Lorena SLS, Pavan CR, Akasaka HMI, Mesquita MA. Beneficial effects of long-term consumption of a probiotic combination of Lactobacillus casei Shirota and Bifidobacterium breve Yakult may persist after suspension of therapy in lactose-intolerant patients. Nutr Clin Pract. 2012 Apr;27(2):247–51. DOI: 10.1177/0884533612440289. PMID: 22402407. Trusted SourcePubMedGo to source
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