The Gut Health Podcast

We map out a clear, practical way to understand IBS-D, from what it is, to how clinicians rule out the conditions that can look like it. With Dr. Anthony Lembo, we move from science to real-world next steps so you can feel more confident about diagnosis, treatment options, and hope for improvement.

• How IBS-D is defined using stool form and pain patterns
• When diarrhea needs more workup using alarm features
• Common IBS-D mimickers including celiac disease, IBD, bile acid malabsorption, microscopic colitis, sucrase isomaltase deficiency and Giardia
• What post-infectious IBS may change in the gut including immune activation, permeability, microbiome, and hypersensitivity
• What the L-glutamine permeability study suggests and what remains unknown
• How to approach it a stepwise treatment IBS-D plan using lifestyle, loperamide, antispasmodics, neuromodulators, rifaximin, and other prescriptions
• Why brain-gut behavioral therapy helps even without severe anxiety or depression
• How we avoid the trap of endless “root cause” chasing with a confident diagnosis

Rome V will include an update of the Rome Criteria (publication available around May 2026).

This episode has been sponsored by Salix Pharmaceuticals.

Follow us on social media, instagram @theguthealthpodcast, where we’d love for you to share your thoughts, questions, and experiences.

References:

Black CJ, Ford AC. An evidence-based update on the diagnosis and management of irritable bowel syndrome. Expert Rev Gastroenterol Hepatol. Published online January 21, 2025. doi:10.1080/17474124.2025.2455586

Marasco G, Cremon C, Barbaro MR, Stanghellini V, Barbara G. Journal of Clinical Gastroenterology Lectureship Dubai 2022 : Management of Irritable Bowel Syndrome With Diarrhea. J Clin Gastroenterol. 2024;58(3):221-231. Published 2024 Mar 1. doi:10.1097/MCG

Congenital Sucrase-Isomaltase Deficiency: What, When, and How?

Foley A, Halmos EP, Husein DM, et al. Adult sucrase-isomaltase deficiency masquerading as IBS. Gut. 2022;71(6):1237-1238. doi:10.1136/gutjnl-2021-326153

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.

Tired of hearing “it’s just stress”? IBS experts Drs. Laurie Keefer and Darren Brenner join Kate Scarlata and Dr. Megan Riehl to set the record straight on irritable bowel syndrome.

IBS is a real, biologically based disorder involving the gut–brain axis, the microbiome, immune function, and nervous system signaling. Understanding how these systems interact reshapes how we diagnose, personalize treatment, and support long-term symptom relief.

If you’ve felt dismissed, confused, or stuck in trial-and-error care, this episode will help you feel validated, informed, and empowered with a clearer, science-backed path forward.

Together we break down:

• The value of a positive diagnosis (not endless testing)
• The impact of trauma and adverse childhood experiences (ACEs) on gut sensitivity
• Using diet to support symptom relief without unnecessary food restriction
• How to comprehensively match treatment to your triggers

Support & Professional Resources

If you’ve experienced ACEs or trauma and want support from a GI psychologist or trauma-informed provider, these directories can help:

• GI Psychology (virtual services available)
• Rome Foundation GastroPsych Provider Directory
• Trauma-Informed Mental Health Provider Directory

Partnering with a clinician trained in gut–brain disorders and trauma-informed care can safely address both physical symptoms and nervous system patterns.

• Aggeletopoulou et al. Unraveling the Pathophysiology of Irritable Bowel Syndrome: Mechanisms and Insights. Int J Mol Sci, 2025.
• Keefer L et al. The Role of Resilience in IBS and Other Chronic GI Conditions. Clin Gastroenterol Hepatol, 2021.
• Chang L et al. Sex, Anxiety, and Resilience in the Association Between Adverse Childhood Experiences and IBS. Clin Gastroenterol Hepatol, 2025.
• Dong et al (UCLA Church Lab). Experiences of discrimination are associated with microbiome and transcriptome alterations in the gut. Front Microbiol, 2024.
• Scarlata K et al. Utilization of Dietitians in the Management of Irritable Bowel Syndrome by Members of the American College of Gastroenterology. Am J Gastroenterol, 2022.
  • How Kate Does It: Low-FODMAP Diet (AJG)

This episode is sponsored by Ardelyx.

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.

Fiber isn’t one-size-fits-all and for some people, more isn’t better. In this episode, we explore why most people under-eat fiber, why certain fibers can worsen symptoms, and how to personalize intake in a way your body can actually tolerate. Dr. Heather Armstrong shares emerging insights on fiber function, microbiome capacity, and practical strategies for going low and slow. We also unpack new science explaining why fiber supports gut health in some individuals, while triggering issues in others with reduced fermentative activity.

In this episode, we discuss:
• The fiber gap, health risks, and minimum intake targets
• How solubility, viscosity, and fermentability guide fiber choice
• Matching fiber types to IBS, diarrhea, and constipation
• Why whole foods matter more than isolates
• Citrus peel pectin and simple kitchen hacks
• Why “low and slow” dosing reduces gas and pain
• How long microbiome changes and symptom relief actually take
• When fiber supplements help (and when they don’t)
• Individualized fiber needs in IBD (and implications for IBS, MS, and liver disease)
• Why dietitians are essential for precision nutrition

This episode is especially relevant if you’ve been told to “just eat more fiber”—and it didn’t go well.

Learn more about Dr. Heather Armstrong's novel research:

Gut feeling: new test and precision diet could boost health for people with IBD. U of A research team in clinical trials for their innovative AI-powered tool that could reduce inflammation by “rewiring” the gut microbiome.

References:

Ramezani F, Pourghazi F, Eslami M, et al. Dietary fiber intake and all-cause and cause-specific mortality: An updated systematic review and meta-analysis of prospective cohort studies. Clin Nutr. 2024

Chang SC, Cassidy A, Willett WC, Rimm EB, O'Reilly EJ, Okereke OI. Dietary flavonoid intake and risk of incident depression in midlife and older women. Am J Clin Nutr. 2016

Armstrong HK, Bording-Jorgensen M, Santer DM, et al. Unfermented β-fructan Fibers Fuel Inflammation in Select Inflammatory Bowel Disease Patients. Gastroenterology. 2023

Armstrong H, Mander I, Zhang Z, Armstrong D, Wine E. Not All Fibers Are Born Equal; Variable Response to Dietary Fiber Subtypes in IBD. Front Pediatr. 2021

Gao J, Lee AA, Abtahi S, et al. Low Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols Diet Improves Colonic Barrier Function and Mast Cell Activation in Patients With Diarrhea-Predominant Irritable Bowel Syndrome: A Mechanistic Trial. Gastroenterology.

This episode is sponsored by Activia.

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.