A careful look at vagus nerve science, autoimmune hope, and where promise still outruns proof.
Ground Truths draws a clean line from Tracy's early TNF work to the point where the brain and immune system sit inside a serious medical field.

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Facts, data, and analytics about biomedical matters. erictopol.substack.com
Based on 6 episodes we listened to · September 2026
Ground Truths makes emerging medical research legible by pressing accomplished guests on mechanisms, evidence limits, and practical consequences.
Eric Topol builds Ground Truths around sustained conversations with researchers and medical thinkers, moving from vagus nerve stimulation and brain clearance to sleep, longevity, and AI in healthcare.
A vagus-nerve gadget sounds different once Eric Topol gets you asking how deep the nerve sits.
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Short reviews from the PlayNext desk, based on the episodes we processed.
A careful look at vagus nerve science, autoimmune hope, and where promise still outruns proof.
Ground Truths draws a clean line from Tracy's early TNF work to the point where the brain and immune system sit inside a serious medical field.
A careful reset on sleep science, drug physiology, and the limits of current human evidence.
Matt Walker and Eric Topol keep this one sober and useful. They revisit what has changed since Why We Sleep, then stay with the hard parts: the glymphatic system, the limits of common sleep drugs, and why natural sleep still has not been fully copied in a pill.
A mechanism-first look at how sleep may help the brain clear waste.
Ground Truths spends most of its time on a simple question: how does the brain clear out what it does not need, and what does sleep have to do with it? The conversation with Dr.
A clear look at AI in medicine, where scaling expertise and copying trust sit uncomfortably close together.
The episode follows Robert Wachter and Eric Topol as they move from AI's promise to its messier medical uses. Mayo Clinic's effort to build digital twins of trusted physicians gives the discussion its clearest anchor, with Dr. Marple cast as a patient-facing avatar.
A measured longevity conversation that keeps asking what is proven, what may come next, and what still needs proof.
Couric and Topol keep the conversation grounded and easy to follow, moving from longevity and evidence-based medicine into the pressure points around anti-science politics, GLP-1 drugs, inflammation, brain health, and AI-based risk prediction.
A longevity conversation that treats sidewalks and street design as public health tools.
Ground Truths treats longevity as a systems problem, not a slogan. It follows Blue Zones from a search for places where people live longest into the Danish twin study, which put genes at roughly 20 to 25 percent of lifespan variance.

Peter Attia evaluates longevity science, from CETP inhibitors to protein debates, through evidence.



Morning medical evidence, compressed for practice.

Medical research, translated through patient experience.

Eric Topol introduces cardiologist Chris Labos, who discusses his book debunking dietary myths and shares a humorous anecdote about emceeing a research awards ceremony.
Owen Tripp shares a personal story from 2016 about misdiagnosed hearing loss and facial numbness, highlighting challenges in finding the right doctor and accessing accurate healthcare.
The hosts introduce authors Bob Bordone and Joel Salinas to discuss their book on conflict resilience, exploring how their law and medicine backgrounds led to interdisciplinary collaboration during polarized times.
Eric Topol introduces Joseph Allen, discussing his background as a former private investigator and FBI applicant before transitioning to public health, focusing on air quality and exposures.
Eric Topol introduces Tyler Cowen as a renowned polymath, discussing his extensive work including books, blogs, podcasts, and his recent writing for The Free Press, while touching on AI tools for learning.
Ardem Patapoutian, a 2021 Nobel Laureate, discusses his challenging childhood in Lebanon during the civil war, including a kidnapping incident.
This segment discusses the bidirectional relationship between sleep disturbances and Alzheimer's disease, including how sleep issues may accelerate the buildup of proteins like amyloid and tau in early stages.
Eric Topol interviews Carl Zimmer about his new book 'Airborne', discussing its inspiration from the COVID-19 pandemic and the challenges in understanding how the disease spreads.
Eric Topol introduces Charlie Swanton, a leading oncology researcher, and begins discussing his early career and PhD work in molecular biology.
Adam Kucharski discusses his book 'Proof', exploring gaps in understanding truth, motivated by his work in health outbreaks and the contrast between mathematical certainty and real-world scientific uncertainty.
This episode segment introduces a discussion on artificial biology and biological intelligence, exploring the convergence of AI and biology through the book 'On the Future of Species' by a molecular biologist and co-founder of Genero.
This segment introduces Dr.
Eric Topol interviews Devi Sridhar about her new book 'How Not to Die Too Soon', discussing global health issues, the gap between health knowledge and outcomes, and the impact of the pandemic on life expectancy.
Eric Topol introduces Anna Greka, a multidisciplinary scientist, and sets up a discussion about her work on rare diseases, particularly focusing on her TED Talk and the MUC 1 discovery.
This segment introduces Lotte Bjerre Knudsen, a key scientist at Novo Nordisk recognized for her work on GLP-1 drugs for obesity and Alzheimer's, discussing her background and the early development of these treatments.
Mark Cuban discusses his efforts to disrupt healthcare by offering low-cost medications through cost plus drugs and critiques the PBM industry for exploiting companies with rebates.
Eric Topol interviews Saesh Kapoor, co-author of the book 'AI Snake Oil', discussing his background as a Princeton PhD candidate and former Facebook machine learning engineer, and the motivation behind writing a book about the realistic capabilities and limitations of AI.
Eric Topol introduces Francis Collins and his new book 'The Road to Wisdom on Truth, Science, Faith, and Trust', discussing its focus on moving beyond hyper-partisan politics to essential sources of wisdom.
Seth Berkley discusses his book 'Fair Doses' and the early days of the COVID-19 pandemic, starting from Davos in January 2020.
Eric Topol introduces Dr.
Eric Doppel introduces and interviews the Glaucomfleckens, a medical comedy duo, discussing their background and rise in popularity through social media and comedy.
This segment discusses a groundbreaking paper on building a virtual cell using AI, featuring authors Charlotte Bunne and Steve Quake, and explores the convergence of AI and biology as the holy grail of the field.
Dr.
The segment discusses whether AI can address problems in medicine, using Jen Lawson's case with Ehlers-Danlos syndrome to highlight financial barriers and healthcare access issues.
Eric Topol interviews Sir John Bell about his career and new role at the Ellison Institute of Technology, focusing on his contributions to life sciences and medicine.
Pradeep Natarajan discusses two new siRNA drugs targeting APOC3 and ANGPTL3 for cardiovascular prevention, based on genetic insights and clinical trials.
Eric Topol interviews Professor Faisal Mahmood about the application of AI and deep learning in pathology, highlighting his background and early advancements in the field.
This segment introduces a discussion with Euan Ashley about the groundbreaking MOTORPACK study, which investigates exercise as a powerful medical intervention through molecular analysis.
Eric Topol interviews Steve Horvath about the accidental discovery of the Horvath epigenetic clock, which uses DNA methylation markers to measure aging across tissues.
This segment discusses the complex personality of Francis Crick as revealed in Matthew Cobb's biography, highlighting his contradictory traits such as being a bohemian philanderer with an open marriage while also engaging in intellectual pursuits and controversial views.
The discussion focuses on the withdrawal of the CDC nominee Weldon, his anti-vaccine stance, and comparisons to RFK Jr.'s controversial views during a measles outbreak.
Dr.
Eric Topol interviews Dr.
Shana Kelley discusses her development of advanced biosensors that enable real-time, continuous monitoring of proteins and inflammation in the blood, building on existing glucose sensor technology.
Eric Topol introduces Dr.
Eric Topol introduces Drs.
Sanjay Gupta discusses his wife's struggle with chronic pain from an autoimmune disease and how a restrictive anti-inflammatory diet, alongside medications like Humira, helped her manage the condition.
Patrick Hsu discusses the founding and mission of the ARC Institute, which focuses on biomedical science and machine learning to address complex human diseases.
Tom Cech discusses his transition from studying DNA to RNA, highlighting RNA's underestimated importance and its exciting discoveries.
Eric Topol introduces Katerina Akassoglou, a neuroimmunologist discussing her research on blood-brain barrier integrity, fibrinogen, and inflammation, with connections to COVID-19 and neurodegenerative diseases.
Eric Topol introduces Shane Crotty to discuss a landmark study on upper airway mucosal immunity, particularly relevant to COVID, published in Nature.
Dan Buettner discusses the 20-year anniversary of his Blue Zones project, explaining how he identified longevity hotspots like Sardinia and Okinawa, the Power Nine lifestyle principles, and addressing recent criticisms of the data.
Sleep scientist Matthew Walker joins Eric Topol to discuss the latest breakthroughs in sleep research, including how sleep deprivation affects social behavior and cooperation, the brain's glymphatic cleansing system, genetic short sleepers, and the surprising effects of different sleep medications on brain health.
Neuroscientist Dr.
Dr.
Eric Topol interviews Robert Wachter about his new book on AI in medicine, covering real-world case studies, the risks of hallucinations, the promise of AI scribes, and why we should judge AI against our imperfect healthcare system rather than an ideal of perfection.
Katie Couric interviews Dr.