Dr. Mary Ellen Sanders, an expert in probiotic microbiology, helps us decode the often confusing world of probiotics, prebiotics, and postbiotics by explaining their scientific definitions, evidence-based benefits, and practical applications for gut health (and beyond).

This episode has been sponsored by Activia.

• Probiotics are live microorganisms that confer health benefits when consumed in adequate amounts
• For something to be called a probiotic, it must be alive, defined to the strain level, and tested in the research setting for health benefits
• When selecting probiotics, look for products with strain designations and doses guaranteed through end of shelf life, not just "at time of manufacture"
• The US Probiotic Guide (usprobioticguide.com) offers independent assessments of probiotic products and their evidence levels, including specific conditions or symptoms
• Specific probiotic benefits include supporting gut function during antibiotic use, reducing respiratory infections, and decreasing crying in colicky babies
• Prebiotics are substrates (often fibers, but also polyphenols) that feed beneficial gut bacteria
• Research suggests about 5 grams of prebiotics daily may be beneficial
• Postbiotics are beneficial preparations of dead microorganisms or their components, challenging the notion that microbes must be alive to benefit health
• When trying probiotics, consult with your health care provider first, as there are some conditions in which they are contraindicated.
• Multi-strain probiotics and synbiotics are commonly available but rarely tested in their exact formulations

References and resources:

• Clinical Guide to Probiotic Products Available in USA http://www.usprobioticguide.com
• Research review: Is There Evidence to Support Probiotic Use for Healthy People? https://www.sciencedirect.com/science/article/pii/S2161831324000991?via%3Dihub
• International Scientific Association for Probiotics and Prebiotics www.ISAPPscience.org
• Perspectives on products combining functional ingredients without testing the product as formulated:
  • Cunningham M, et al.. The influence of product formulation on the activity and clinical outcomes of probiotic and prebiotic products. Trends Food Sci Technol: 112, June 2021, Pages 495-506.
  • Sanders ME, et al. 2014. Effects of genetic, processing, or product formulation changes on efficacy and safety of probiotics. Ann N Y Acad Sci. 1309(1):1-18.
• Probiotic product survey:
  • Merenstein DJ, Guzzi J, Sanders ME. 2019. More Information Needed on Probiotic Supplement Product Labels. J Gen Intern Med. 34(12):27

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Dr. Mark Pimentel, Executive Director of the MAST program at Cedars-Sinai in Los Angeles, shares groundbreaking insights into the small intestinal microbiome that challenge long-held beliefs about gut bacteria. Findings from his team’s REIMAGINE study reveal that the small intestine is far from sterile, as previously thought—instead, it harbors substantial bacterial communities that play a critical role in health and disease, especially in conditions such as IBS and SIBO.

• E. coli and Klebsiella act as aggressive "Ferrari" bacteria that outcompete other microbes and destroy microbial diversity when overgrown inducing a "apocalyptic" disruption of the small bowel microbiome.
• Lactobacillus, commonly found in many probiotics, may act as a disruptor in the small intestine and new research correlates higher small intestinal levels with obesity and unhealthy aging (more research needed)
• The PLACIDE trial found probiotics didn't reduce C. diff or antibiotic-associated diarrhea but did increase bloating
• Food poisoning is the only proven cause-and-effect trigger for IBS, with stress acting as a modifier rather than initiator
• Combining rifaximin with NAC works 10x better for SIBO by targeting bacteria in both intestinal fluid and mucus
• A new compound (CS06) shows promise for reducing methane production and relieving constipation
• Three distinct gas patterns (hydrogen, methane, hydrogen sulfide) correlate with different symptom patterns and respond to targeted treatments

This episode was sponsored by Salix Pharmaceuticals.

Resources:

DDW 2025 Abstracts by the Mast Program and Dr. Pimentel

A Novel Microbiome Therapy, CS-06 (MTD Blocker), Reduces Methane Production in Stool Culture

Real World Study of Three-Gas Breath Testing Nationwide and The Association with Symptoms

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Dr. Iris Wang of the Mayo Clinic shares cutting-edge insights on gut health across the lifespan, including advancements in pharmacogenomics for personalized medication selection and innovative breathing techniques to relieve abdominal distension. She busts common myths about bloating, revealing how diaphragmatic dysfunction rather than excess gas may be the culprit. Dr. Wang also emphasizes the importance of starting gut health education early, helping kids and parents alike understand that pooping shouldn't be painful or forced.

• How pharmacogenomics helps identify why some patients metabolize medications differently, leading to better medication choices with exploration on the hope and/or hype of precision medicine in the GI world (Wang et al 2019)

• Explanation of abdomino-phrenic dyssynergia (APD) – when the diaphragm moves downward instead of upward, causing visible abdominal distention

• Specialized breathing technique developed in Barcelona that retrain the diaphragm for bloating relief (Barba E et al 2024) - see video link below

• The importance of normalizing healthy pooping habits from childhood through education & tools like toileting stools (e.g. Squatty Potty)

• Warning signs for parents about childhood constipation – including stool leakage, straining, & urinary problems (Tran DL et al 2023)

• How yoga can support gut health through mindful movement, core engagement, & stress reduction

Yoga videos:

Yoga For Digestion Flow| Yoga With Adriene (26 mins)

Yoga for Bloating, Digestion, Ulcerative Colitis, IBD & IBS (12 mins)

Check out Dr. Wang's children's book Boo Can't Poo, which helps normalize healthy pooping habits for kids while educating parents too.

References:

Wang XJ, Camilleri M. Personalized medicine in functional gastrointestinal disorders: Understanding pathogenesis to increase diagnostic and treatment efficacy. World J Gastroenterol. 2019 Mar 14;25(10):1185-1196.

Barba E, Livovsky DM, Accarino A, Azpiroz F. Thoracoabdominal Wall Motion-Guided Biofeedback Treatment of Abdominal Distention: A Randomized Placebo-Controlled Trial. Gastroenterology. 2024;167(3):538-546.e1.

Specialized breathing technique for abdominal distention: Video Demonstration

Tran DL, Sintusek P. Functional constipation in children: What physicians should know. World J Gastroenterol. 2023 Feb 28;29(8):1261-1288.

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Fermented foods offer surprising health benefits with science showing they can increase gut microbial diversity in ways other dietary interventions cannot.

• Expert Elisa Caffrey clarifies what qualifies as fermented food: substrate + microbes + time
• While touted as a source of probiotics, most fermented foods don't technically contain probiotics, which require specific strain characterization and known health benefits
•Different types of fermentation are used in food production: lactic acid bacteria ferment carbohydrates in sauerkraut and yogurt; acetic acid bacteria oxidize ethanol into acetic acid in kombucha; and filamentous fungi such as Aspergillus oryzae and Rhizopus species are involved in the fermentation of miso and tempeh, respectively.
• Fermented foods may benefit gut health through microbial derived metabolites rather than just the microbes in the food or beverage.
• Consider starting with yogurt if you are a newcomer and have fun exploring kimchi, sauerkraut and other options for fermented food variety.
• Most fermented foods are safe, though some considerations exist for those with histamine intolerance or sodium restrictions
• Variety is key – consuming diverse fermented foods appears to help maximize potential benefits
• The fermentation process may have mental health benefits beyond nutrition though more research is needed

Try incorporating fermented foods gradually into your diet and experiment with different types to find what works for your body and taste preferences.

Let us know what makes your taste buds (and gut) happy!

This episode has been sponsored by Activia. Check out their Gut Health Tool Kit here and A Gut Friendly Meal plan here.

References:

Caffrey EB et al. Unpacking food fermentation: Clinically relevant tools for fermented food identification and consumption

Gaudiest G et al. Microbial and metabolic characterization of organic artisanal sauerkraut fermentation and study of gut health-promoting properties of sauerkraut brine

Wastyk HC et al. Gut microbiota-targeted diets modulate human immune status (high fiber vs fermented food study)

Nielson ES et al. Lacto-fermented sauerkraut improves symptoms in IBS patients independent of product pasteurisation - A pilot study

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Pelvic floor physical therapy (PFPT) is a crucial yet often overlooked component of gut health that can dramatically improve quality of life for people suffering from bowel issues, bladder problems, or pelvic pain. Dr. Alicia Jeffrey-Thomas joins us to demystify and normalize this specialized therapy and explain how proper pelvic floor function impacts everything from constipation to sexual health.

• Understand that daily bowel movements don't necessarily mean you're not constipated
• What happens during a PFPT session and how therapists create a safe + comfortable environment
• The importance of proper pooping position
• Why breathing techniques and sounds (like mooing!) can help relax your pelvic floor during bowel movements
• Demystifying tools like pelvic wands and dilators for at-home maintenance
• How dyssynergic defecation affects approximately 50% of people with constipation and how pelvic floor PT can help
• Why all women can benefit from pelvic floor PT after childbirth (and even during pregnancy)
• Men face pelvic health issues too, like post-prostate surgery incontinence
• The downside of "peeing just in case" and how it trains your bladder to signal fullness prematurely

If you've experienced pelvic floor issues, don't accept them as normal - seek help from a pelvic floor physical therapist who can address these problems and improve your overall quality of life.

References and Resources:

Rao SS, Patcharatrakul T. Diagnosis and Treatment of Dyssynergic Defecation. J Neurogastroenterol Motil. 2016 Jul 30;22(3):423-35. doi: 10.5056/jnm16060. PMID: 27270989; PMCID: PMC4930297.

Ye AL, Johnston E, Hwang S. Pelvic Floor Therapy and Initial Interventions for Pelvic Floor Dysfunction in Gynecologic Malignancies. Curr Oncol Rep. 2024;26(3):212-220. doi:10.1007/s11912-024-01498-6

Where to find a pelvic floor PT:

• https://pelvicrehab.com/
• https://pelvicglobal.com/directory/

Alicia Jeffrey-Thomas' book, Power to the Pelvis.

Got constipation? Check out Kate's constipation guide.

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Join us as we discuss effective non-diet focused methods for IBS relief. In this episode, Kate and Dr. Riehl review key factors on how gender can influence common symptoms of IBS.

Hormones significantly influence IBS symptoms, with women being diagnosed 2.5 times more often than men, in part due to differences in gut function and pain perception.

This episode features the following key discussion areas:

• Women's fluctuating estrogen and progesterone levels affect gut motility and pain sensitivity throughout the menstrual cycle
• Visceral hypersensitivity causes normal digestive sensations to be interpreted as pain - like a car alarm going off unnecessarily
• The "microgenderome" refers to gender differences in gut microbiome that may contribute to women's higher rates of IBS and autoimmune conditions
• Gut-directed hypnotherapy helps reprogram the subconscious mind to interpret gut sensations more accurately, with 70-80% improvement rates
• Pelvic floor physical therapy can help address muscle tension that contributes to both constipation and diarrhea symptoms
• Non-diet approaches including medications, supplements like enteric-coated peppermint, and lifestyle factors are effective IBS management tools
• Regular exercise (especially in nature), adequate sleep, and stress management techniques complement other treatments

For more information on IBS-C treatments, check out our dedicated three-part series in episodes 14, 15, and 16.

This podcast has been sponsored by Ardelyx and Nerva by Mindset Health.

References:

Mulak A, Taché Y, Larauche M. Sex hormones in the modulation of irritable bowel syndrome. World J Gastroenterol. 2014;20(10):2433-2448. doi:10.3748/wjg.v20.i10.2433

Chang L, Heitkemper MM. Gender differences in irritable bowel syndrome. Gastroenterology. 2002;123(5):1686-1701. doi:10.1053/gast.2002.36603

Houghton LA, Jackson NA, Whorwell PJ, Morris J. Do male sex hormones protect from irritable bowel syndrome?. Am J Gastroenterol. 2000;95(9):2296-2300. doi:10.1111/j.1572-0241.2000.02314.x

Peters SL, Yao CK, Philpott H, Yelland GW, Muir JG, Gibson PR. Randomised clinical trial: the efficacy of gut-directed hypnotherapy is similar to that of the low FODMAP diet for the treatment of irritable bowel syndrome. Aliment Pharmacol Ther. 2016;44(5):447-459. doi:10.1111/apt.13706

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

Is "leaky gut" real or just another wellness buzzword? In this episode of The Gut Health Podcast, we cut through the controversy with Dr. Alessio Fasano, a renowned gastroenterologist and microbiome expert from Mass General Brigham. Dr. Fasano explains what happens when the gut’s protective barrier is compromised, resulting in increased intestinal permeability, and how this can affect not only gut health but also overall well-being.

While some level of intestinal permeability is essential for health, in the presence of an altered gut microbiome, it can allow harmful molecules such as bacterial endotoxins and undigested food particles to pass through the intestinal lining. This can lead to inflammation, immune system activation, and may contribute to a variety of health issues, including autoimmune diseases, gastrointestinal disorders, heart disease, and more.

We explore the molecular mechanisms that control intestinal permeability, examining how factors like epigenetic changes, diet, stress, and environmental factors can all impact the integrity of the gut barrier. Dr. Fasano breaks down the latest research on how intestinal permeability interacts with the immune system and other organ systems, highlighting the complex bidirectional relationship between gut health and overall wellness.

Join us as we explore cutting-edge research on gut health, from breakthrough treatments to personalized diets and biomarkers for gut permeability. Tune in for expert insights and practical strategies—like a plant-forward diet and stress management—to strengthen your gut and overall well-being.

References:

Effects of dietary components on intestinal permeability in health and disease.

Unfermented B-fructans Fibers Fuel Inflammation in Select Inflammatory Bowel Disease Patients.

High FODMAP diet causes barrier loss via lipopolysaccharide-mediate mast cell activation

A Randomized Placebo-Controlled Trial of Dietary Glutamine Supplements for Post-Infectious Irritable Bowel Syndrome.

Bovine Colostrum in Increased Intestinal Permeability in Healthy Athletes and Patients: A Meta-Analysis of Randomized Clinical Trials.

What to do about the leaky gut?

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.

What if you could navigate the complexities of IBS without falling into restrictive habits or feeling overwhelmed? Join us for an insightful conversation with Erin Judge, a registered dietitian nutritionist as she shares her compelling journey from childhood challenges with IBS-C to becoming an advocate for patient-centered care. Erin opens up about her early experiences with gastrointestinal issues, exacerbated by a Giardia infection painting a vivid picture of the emotional and physical hurdles she faced living with the complexities of IBS, in a time in which, IBS research and treatment modalities were limited.

Erin's story is a testament to resilience and the important ways resources for IBS management have evolved over the last decade. She reflects on how understanding balanced nutrition, avoiding restrictive habits and adopting an enriched lifestyle have been key to her management strategies.

Listeners will gain valuable insights into practical strategies for constipation relief, emphasizing the gut-brain connection's role in managing symptoms. Erin discusses the significance of lifestyle adjustments, such as movement, adequate hydration, supportive dietary changes, and stress regulation, offering a toolkit to empower individuals facing similar challenges. By sharing her knowledge and experiences, Erin aims to foster hope and confidence, encouraging a guilt-free approach to health and wellness for those living with IBS.

Learn more about Kate and Dr. Riehl:

Website: www.katescarlata.com and www.drriehl.com
Instagram: @katescarlata @drriehl and @theguthealthpodcast

Order Kate and Dr. Riehl's book, Mind Your Gut: The Science-Based, Whole-body Guide to Living Well with IBS.

The information included in this podcast is not a substitute for professional medical advice, examination, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider before starting any new treatment or making changes to existing treatment.