Today, I'm joined by Dr. Grace Liu, often known as the “Gut Goddess,” a trailblazer in the world of microbiome science and founder of The Gut Institute. In this conversation, we take a bold dive into an often-overlooked pillar of longevity: your poop. That's right—Dr. Liu unpacks the fascinating and sometimes surprising science showing how gut health shapes everything from your immune system and brain to your lifespan itself. Episode Timestamps: Introduction to host... 00:00:00 Dr. Grace Liu on the gut as a hallmark of aging... 00:04:06 Peptides, FMT, and evidence for gut-driven regeneration... 00:05:04 FMT safety, immune education, and the environmental “microdosing” effect... 00:07:07 Links between gut aging, the immune system, and mental health... 00:08:13 Diet, ancestry, and resistant starch for butyrate production... 00:15:01 Ancestral diet, microbiome differences, and pitfalls of shortcuts... 00:18:53 Fiber, polyphenols, and the key longevity bacteria... 00:24:09 Gut markers, loss of diversity, and ABC species signature... 00:25:15 Risks of overhyped probiotics, strep, and broad interventions... 00:36:29 Peptides, bioregulators, and repairing the gut... 01:12:01 Practical longevity: movement, daily habits & where to learn more... 01:22:46 Our Amazing Sponsors: Tro Zzz by Troscriptions – A fast-acting sleep troche that dissolves in your cheek and combines melatonin with compounds like honokiol, adenosine, cordycepin, CBD, CBN, and 5-HTP to support deep, restorative sleep when travel, stress, or late workouts throw things off. Head to troscriptions.com and use code NAT10 for 10% off your first order. O₃RACLE by Wizard Sciences — A daily ozonated oil capsule designed to support immune balance, cellular communication, and antioxidant production without clinics, machines, or complicated routines; learn more at wizardsciences.com and use code NAT15 for 15% off. CP1 Pure Collagen Peptides by Puori — a clean, unflavored collagen that supports connective tissue, joints, and skin elasticity with a unique amino acid profile your body actually uses, plus full third-party testing; go to puori.com/NAT and use code NAT for 32% off when you start a subscription. Nat's Links: YouTube Channel Join My Membership Community Sign up for My Newsletter Instagram Dr. Bill Lawrence Episode