45. Case Study: SIBO, Histamine Intolerance & Hormonal Imbalance

In this episode of The Histamine Well, Joanne shares a powerful clinical case study exploring the connection between SIBO (Small Intestinal Bacterial Overgrowth), histamine intolerance, hormonal imbalance, estrogen dominance, gut health, bloating, acne, fatigue, and PMS symptoms.

This episode follows the journey of a 37-year-old woman who experienced rapid body changes over two years — including unexplained weight gain, chronic bloating, severe PMS, hormonal acne, headaches, fluid retention, breast tenderness, digestive discomfort, and low energy. Through functional testing and a naturopathic treatment approach, Joanne uncovers how gut dysfunction, histamine overload, and hormone imbalance can work together to drive chronic symptoms.

You’ll discover how SIBO contributes to nutrient malabsorption, inflammation, estrogen dominance, histamine intolerance, and digestive dysfunction, along with why symptoms such as bloating, fatigue, skin issues, and menstrual changes are often connected.

In this episode, Joanne discusses:

• The link between SIBO, histamine intolerance, and hormonal imbalance
• Why bloating, PMS, headaches, and acne may stem from gut dysfunction
• The difference between hydrogen and methane SIBO
• How nutrient deficiencies affect hormones, mood, and energy
• Why is bowel motility essential for successful SIBO treatment
• The role of biofilms in persistent gut symptoms
• Functional medicine strategies for improving gut and hormone health

Whether you are a practitioner, student, or someone navigating digestive and hormone-related symptoms, this episode offers practical insight into the deep connection between gut health, histamine, hormones, and systemic inflammation.

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Transcript

0:00

Hi, it's Joanne. What if the symptoms you've been dealing with, bloating, weight gain, acne, PMS and fatigue aren't separate issues at all. But part of the same underlying pattern. Because when gut health, histamine and hormones start to overlap, things can become complex very quickly. And they're often missed when each piece is treated in isolation. In today's episode, I'm talking you through a real clinical case that brings all of this together. Whether you are a practitioner or someone navigating your own health, this is one of those cases that shifts how you see complex presentations, and once you see it, you really can't unsee it. Welcome to the Histamine Well Podcast. Designed for practitioners and patients alike. This is your trusted source for insights on histamine intolerance, methylation, gut health, women's hormones, and much more. I'm Joanne Kennedy. Your host, naturopath, author, and educator. Passionate about breaking down complex science into clear, accessible knowledge. Whether you are a health professional or navigating your personal wellness journey, the Histamine Well Podcast bridges the gap between cutting edge research and practical understanding to empower you with the tools to thrive. Hi everyone. Welcome back to the histamine well. Before I start, I just wanna mention that there's bird noises here today. So you can hear in the background. I think I can hear in the background when I listen to it with my earphones on. But they're sweet little birds. I hope you don't mind, and I just don't fancy jumping into a cupboard to do the show, so i'm sure it won't distract you. So today I'm gonna walk you through a really powerful case that ties together gut health, histamine, and hormonal imbalance. And it shows you just how connected all of these systems really are. So it's a lovely patient of mine, a 37-year-old female who came in saying, and these are her own words, my body has changed rapidly over the past two and a half years. I've gained weight, I'm constantly bloated. My PMS is out of control. My energy is low. My skin is terrible, and I have constantly getting headaches. So when we went through her case, she reported also that she was getting lower abdominal discomfort and cramping. She was getting heavy periods. She was getting significant fluid retention about seven to 10 days before her period. Really sore breasts about five days before her period. She felt really emotional. Very teary. Premenstrually, she had a regular 28 day cycle. From a gut perspective, she said she was constantly bloated. She was having daily bowel motions, but excessive flatulence. And she did have that lower abdominal pain as well. And so the other symptoms. Which I will flag in my mind are histamine symptoms unless proven otherwise. But I'm always thinking about histamine. She was getting headaches. Acne on her arms and her back. Cyclical cystic acne on the chin around ovulation and premenstrually. Her energy was only about 6 out of 10. She had a lot of fatigue after eating. She had tingling in her hands and feet. And she had muscle cramps. And I must say in her diet, she was consuming a lot of soy products, which is really relevant given the hormonal picture. So soy is very estrogenic in menstruating women. We learn about this in research. There's a lot of research on soy and hormones and estrogen. But I tell you what, when you are an estrogen dominant woman, you don't wanna be having too much soy. It can really, really increase the amount of circulating estrogen in your body. So when I look at this case, constant bloating, flatulence. Like it's so classic sibo. And it also can just cause weight gain. It can also just drive up histamine. So SIBO is something I thought is definitely an issue. She has a regular cycle. She's only 37. She's has all the symptoms of estrogen dominance. Weight gain around the hip, thighs and abdomen. Fluid attention. Breast tenderness. Tingliness. It's classic estrogen dominant symptoms. What I did for her straight away is I sent her off for SIBO testing. As well as some bloods from the doctor. Including a full blood count, biochemistry, iron studies, vitamin D, and active B12. So why did it do that? I wanna see what type of SIBO it is. I wanna know if it's methane. I want to know if it's hydrogen. She doesn't have symptoms really of hydrogen sulfide sibo. So I wanna see what's there. How high the levels are. And blood work, I want to see iron. Iron helps make progesterone. SIBO is a massive cause of iron malabsorption. She's really, really tired. So I wanted to see. Vitamin D, I wanted to see. Because it is really important for mood and it's really important for making progesterone. I really wanted to see her active B12 again because that can actually be decreased with sibo. She's getting tingling in hands and feet. That is a classic sign of B12 deficiency. I wanted her to do like her biochemistry, which gives her us the electrolytes. I wanted to see what her Anion gap is, which is a marker of acidity. And because acidity, well, it disrupts your hormone significantly. So I really wanted to see what her Anion gap is. I also started her on the SIBO diet straight away. So she did the test and then they did the diet. I often do that. I'm so convinced she's got SIBO and I want her just to start, get some relief so that when I see her at the follow-up, she's had some improvements. We can see if there's anything we need to tweak. And then we have the test results back and we haven't sort of wasted a couple of weeks. Now, I didn't put her on a SIBO low histamine diet like I could have. So I've got a SIBO diet and a sibo, low histamine. Now, if people are they're getting like migraines. Or they're covered in eczema. Or they have a really bad reflux, like more sort of severe debilitating histamine symptoms. I probably would get them on a sibo, low histamine diet, but I felt confident with her that if we just get the SIBO down, we're gonna get the histamine down. If we're gonna detoxify that estrogen, then we are going to get the histamine down as well. And what I gave her to detoxify her estrogen was calcium D glucarate. I got her to take it from day seven to bleed. I don't get women to take it every day Because it can drop your estrogen too much. But she seemed like a candidate to be able to take it from day seven right through to bleed. And I also gave her a supplement from Metagenics called PMS ease. It has Vitex in it, zinc, B6 and iodine, all really important for progesterone production. And then I tested her iron and vitamin D as both are required for healthy progesterone production. And so they need to be dealt with separately if they came back low. So on our second appointment, her test results came back. High hydrogen, high methane. So we've got a mixed SIBO picture. And clinically, her symptoms were already improving. Bloating was significantly reduced. Flatulence reduced. No headaches. And she also worked out that having coffee with oat milk was what was causing her lower abdominal pain. Now, her bowels, however, had slowed. Now this is something you really need to watch with a low FODMAP diet, which is a SIBO diet. It's low in fiber. I. So it can often happen that a bit of constipation can creep in if we don't get the fiber intake up. So you've gotta try your hardest with the vegetables that you can eat. But what is great for this is partially hydrolyzed guar gum, which is a prebiotic fiber that is low fodmap. So I definitely added that into her prescription. I also gave her berberine for hydrogen sibo. Allicin for methane. And I also got her on a supplement from Research Nutritionals called Biodisrupt. This helps break down biofilms that protect SIBO bacteria. So an important clinical note is that SIBO organisms can form biofilms, which make them resistant to treatments. Addressing the biofilm is really, really important. Before we go any further, I want to speak directly to the practitioners and students listening. If you're intrigued by histamine and methylation and eager to expand your knowledge in this fascinating area, we offer the Histamine and Methylation online group coaching course. The only program of its kind. It covers everything you need to know about histamine and methylation, providing both the theory and guidance you need to treat these issues effectively in clinical practice. We cover sibo, hormonal imbalances, oxalates, M-T-H-F-R, the four pathways of methylation, including the folate pathway, methionine pathway, tetra hydrobiopterin pathway, and the all important transsulfuration pathway and much more. The program is delivered by detailed online webinars and handouts for you to keep. And for eight weeks you'll meet with me for live coaching calls in a private community space with other practitioners from all over the world dealing with histamine and methylation issues in their patients every day. Together we learn so much. To learn and apply, visit joanne kennedy naturopathy com. Now her vitamin D came back at like 80, which is good. Her iron, surprisingly her ferritin was 48. So we don't need to supplement, which is great Because you don't wanna supplement with SIBO Because it can promote bacterial overgrowth, contribute to biofilm formation. If a woman's ferritin is like at eight, I, I kind of do supplement with iron because they're so exhausted they can't. Actually get the energy to even get to the supermarket to buy the foods that they need to eat. So it's just a bit of a clinical dilemma and a case by case. But this girl didn't need iron, which was great. Her active B12 was actually low, and she had a high anion gap. So I added in some sublingual B12 and I added in some electrolytes. The one I use is Basica. So I sent her off and I wanted to see her two weeks later, mainly because her bowels were not moving. Bowels have to move with a SIBO treatment. I can't tell you how many patients I've seen that do a SIBO diet for so long, or take antibiotics for SIBO and their bowels aren't moving. It's not gonna go. If the bowels aren't moving, you need to be pooping out the undigested food and bad bacteria. Super important to get that right. So next consult. Her bowels were good. Moving with the partially hydrolyzed gu gum. No bloating, no abdominal pain, no headaches. Her skin was improving significantly. Her acne was still appearing but resolving much faster. So it was like coming up, but like then sort of when her hormones changed, but then would not flare as badly and it would reduce. And this is a key clinical sign that inflammation and histamine are reducing. So I like this case because most people don't understand how much histamine drives acne. Histamine receptors exist in sebaceous glands, which like produce the sebum that causes acne. And it increases oil production and inflammation. It's not just pCOS picture and high androgens that can cause acne. High estrogen, and high histamine can really cause acne. She also reported improved energy, better sleep, no tingling in hands or feet or muscle cramps. You'll see that once you get your B12 up and your electrolytes in, that's classic. That will really, really start to help. Weight was starting to drop from her abdomen, hips, and thighs. Breast tenderness is gone. She wasn't feeling puffy and fluid retention before her period. She felt emotionally stable premenstrually. So at this point, everything was moving in the right direction. Gut was improving histamines reducing, hormones, rebalancing. Now, I was happy to let this girl go off for the, about the four months that you need to clear SIBO. Because she had the diet right, she was compliant, she was tolerating the supplements, her bowels were moving. So I did check in with her a couple of times in that time. But it takes about four months to get SIBO cleared. So at four months we retested it was gone and she said, I haven't felt this good in years. Her weight returned to baseline. No bloating, no abdominal pain, no histamine symptoms. Hormones were really stable. Her skin was almost completely clear. Only one small pimple during ovulation. So what I do now is I start reintroducing the FODMAP foods. And look, if sibo, we've tested it and it's gone. People just don't react to the fodmap. But we just reintroduce them slowly and make sure that they're fine. And then I just wean her off the supplements. So usually people have a lot of supplements sort of left. They're halfway through them. They just can finish them off. Saying that I did get her to stay on the Basica. The Calcium D Glucarate and the PMS Ease for her hormones. And we booked her in for a follow up in six months time, just to have a check-in to see how she's going on those supplements. Because some women can be on those supplements for several years. Until they're sort of in their mid forties when their hormones will change again. But I just like to check in with my female patients every six months or so when they're on these hormone supplements to make sure we are still doing the right thing. So key clinical takeaways or case highlights. It's very simple. SIBO absolutely drives up histamine. It causes nutrient malabsorption. It contributes significantly to estrogen dominance. It contributes to systemic inflammation. So we have symptoms such as bloating and fatigue, malabsorption of nutrients, PMS, weight gain, headaches, acne. So SIBO is such a driver of so many symptoms. You know, it is so common. It's the main cause of IBS globally. It's so often missed from doctors, and unfortunately I need to say it from many naturopaths and nutritionists and integrative doctors who are just focusing on doing stool testing. And when someone has malabsorption of nutrients, well, that's the small bowel is where you absorb nutrients, the majority of them. And when you have a lot of histamine symptoms with the bloating and the flatulence, classic symptoms of sibo. So if you need help with your gut, with your skin, with your hormones, we are here to help. We see patients online globally. You can easily make an appointment via my website, joanne kennedy naturopathy.com. So thank you for joining me. I hope you found this episode beneficial. Be sure to subscribe to the histamine well so you don't miss an episode. Leave a review and you can also share this episode with someone who could benefit. If you have any questions you'd like answered or have a topic you'd like me to discuss, please go to my website, joanne kennedy naturopathy.com, where you can provide us with that information. Until next time, take care and be well.