RHR: Vitamin D: Why a Personalized Approach Is Best

In this episode of Revolution Health Radio, Chris sits down with gastroenterologist and microbiome researcher Dr. Zain Kassam to explore the rapidly evolving science of the microbiome and its profound impact on sleep, circadian rhythm, cognitive performance, stress resilience, immune balance, and longevity. From groundbreaking research on microbiome diversity and sleep quality to emerging innovations like cobiotics, Dr. Kassam explains how our microbial partners regulate core biological systems far beyond the gut. They discuss the connection between the gut and the brain, eyes, skin, and even ears—along with practical strategies for supporting microbial health in a modern world that constantly disrupts it. The post RHR: Beyond the Gut: The Microbiome’s Role in Sleep, Energy, and Longevity, with Dr. Zain Kassam appeared first on Chris Kresser.

Depression and anxiety are often treated as chemical imbalances in the brain—but what if the real problem starts in the gut? In this episode of Revolution Health Radio, we dive deep into the gut–brain connection and the growing body of research linking gut inflammation, microbiome imbalance, and mood disorders. You’ll learn how inflammatory cytokines contribute to depression, why butyrate is emerging as a powerful antidepressant compound, and how specific probiotic strains can improve mental health outcomes. Chris also shares practical, evidence-based strategies—including diet, supplementation, and functional testing—to address root causes and support lasting emotional well-being. The post RHR: The Gut-Brain Connection: How Your Microbiome Affects Your Mental Health appeared first on Chris Kresser.

In this episode of Revolution Health Radio, Chris Kresser explains why vitamin D supplementation should never be one-size-fits-all. Drawing on new research—including a groundbreaking study on magnesium’s regulatory role—Chris explores how genetics, ethnicity, body weight, age, health status, sun exposure, and nutrient cofactors all shape an individual’s vitamin D needs. He outlines optimal testing strategies, safe and effective target ranges, and the critical roles of magnesium, vitamin K2, and vitamin A in vitamin D metabolism. The episode reframes vitamin D optimization as a personalized, systems-based approach that prioritizes balance, testing, and real-world physiology over generic dosing guidelines. The post RHR: Vitamin D: Why a Personalized Approach Is Best appeared first on Chris Kresser.

Cold plunges and ice baths dominate social media, but do they really deliver the best metabolic benefits? In this episode of Revolution Health Radio, Chris Kresser challenges the “colder is better” narrative and explores what the science actually shows about cold exposure. Drawing on clinical research, he explains how brown adipose tissue works, why sustained mild cold exposure activates it more effectively than brief extreme cold, and how this can improve insulin sensitivity, glucose metabolism, and overall metabolic health. The post RHR: Cold Exposure: Why Sustained Beats Extreme appeared first on Chris Kresser.

In this episode of Revolution Health Radio, Chris challenges the conventional focus on sleep duration and makes the case that sleep timing and circadian alignment matter just as much—if not more—than total hours slept. Drawing on new research, he explains how circadian disruption underlies poor sleep quality, chronic fatigue, and a wide range of mental health conditions, even in people who appear to be doing everything “right.” He explains why light exposure, sleep-wake consistency, and meal timing are the primary drivers of restorative sleep, why adolescents are uniquely vulnerable to sleep-related mental health risks, and shares practical strategies to improve sleep naturally and when supplements may be helpful. The post RHR: Why Your Sleep Schedule Matters As Much As Duration appeared first on Chris Kresser.

In this episode of Revolution Health Radio, Chris examines research confirming that menopause-related brain fog is real, measurable, and reversible. He explains how gray and white matter changes, blood-flow disruption, inflammation, and declining estrogen impact cognitive function during perimenopause and menopause. He also highlights the critical role of the gut microbiome in regulating estrogen metabolism and influencing brain health, and provides listeners with a comprehensive, root-cause approach to improving memory, focus, and clarity through diet, exercise, stress management, sleep, targeted nutrients, and gut-supportive strategies. The post RHR: Menopause Brain Fog—What’s Really Happening (and How To Fix It) appeared first on Chris Kresser.

Seed oils have become one of the most controversial topics in nutrition, especially after a 2024 University of South Florida study linked high omega-6 levels with inflammation in colon tumors. In this episode of Revolution Health Radio, Chris takes a deep, evidence-based look at what the study actually means — and what it doesn’t. You’ll learn the crucial difference between naturally occurring omega-6 fats in whole foods like nuts, chicken, and avocados and oxidized omega-6 fats found in ultra-processed foods and industrial seed oils. He explains why awareness of the omega-6 to omega-3 ratio and the issues of the modern Western diet are far more important than demonizing individual oils and offers practical advice on which cooking oils to use, which to limit, how to improve omega-3 intake, and how to adopt a balanced approach to dietary fats without fear or obsession. The post RHR: Seed Oils and Colon Cancer – What the New Research Really Shows appeared first on Chris Kresser.

In this episode, Chris explains why obsession with anti-aging hacks may actually undermine our long-term health. He examines the common longevity traps people fall into, which foundational habits truly extend lifespan and health span, and outlines a simple framework for prioritizing what really works. If you’re overwhelmed by conflicting longevity advice, this episode brings clarity, realism, and a grounded path forward. The post RHR: The Longevity Trap: Why Chasing Anti-Aging May Be Aging You appeared first on Chris Kresser.

In this episode of Revolution Health Radio, Chris welcomes psychiatrist Dr. Matt Bernstein to explore the emerging field of metabolic psychiatry, the science linking brain energy metabolism to mental health. They discuss how conditions like depression, bipolar disorder, schizophrenia, and anxiety often share a root cause in impaired brain energy production, and how ketogenic therapy can restore balance and improve outcomes where traditional treatments fall short. Chris and Dr. Bernstein also unpack the latest research, the mechanisms behind ketones’ impact on the brain, and practical considerations for adults, teens, and families exploring this approach. The post RHR: The Link Between Metabolic Health and Mental Well-Being, with Dr. Matt Bernstein appeared first on Chris Kresser.

In this episode of Revolution Health Radio, Chris explores natural solutions for one of today’s most pressing challenges: chronic stress, anxiety, and poor sleep. He shares his top five nutrients for restoring calm and focus (saffron, L-theanine, lemon balm, holy basil, and ashwagandha), revealing how each supports the brain and body’s ability to relax, recharge, and build resilience. Drawing from both scientific research and clinical experience, Chris explains how these compounds balance neurotransmitters, reduce cortisol, and improve mood and sleep quality without sedation or dependence. Listeners will learn practical strategies for combining these nutrients safely and effectively to achieve steady energy, emotional balance, and deep, restorative rest. This episode offers a roadmap to move from wired and tired to calm and clear, using evidence-based tools rooted in both modern science and ancient wisdom. The post RHR: From Wired & Tired to Calm & Clear: My Top Nutrients for Mood, Focus, and Sleep appeared first on Chris Kresser.