Your Habits in Your 30s Are Writing Your Alzheimer's Diagnosis in Your 70s | Dr. Jonathan Fellows

🧠 Stay ahead with the latest in science, nutrition, and wellness by subscribing to Dr. Perlmutter’s newsletter at: www.drperlmutter.com. ✉️🌱 Thank you to our sponsors: EVY - https://www.optoceutics.com/perlmutter and the code perlmutter26 will be auto-applied to your order to get $200 off & free shipping (90 days risk-free). 3x4 Genetics - https://3x4genetics.com/DrPerlmutter for a special offer when you sign up to decode your genetics and get personalized, science-backed health recommendations. ==== Dr. Perlmutter’s groundbreaking new book, Brain Defenders, is now available for pre-order. Discover how to protect your brain and future health - reserve your copy today at https://www.braindefenders.com. What if the gene you've been told to fear isn't actually a verdict on your future, and the disease you're racing to treat has already been silently progressing for two to three decades before anyone notices? In this episode, Dr. Jonathan Fellows joins me to challenge how we think about Alzheimer's risk, diagnosis, and treatment, making the case that early detection and lifestyle intervention matter more than the medications most people pin their hope on. We dig into why amyloid in the brain alone does not equal an Alzheimer's diagnosis, what the P-tau 217 blood test reveals decades before memory loss begins, why telling a patient their APOE4 gene is a death sentence is, in his words, malpractice, how insulin resistance and blood sugar dysregulation quietly drive brain degeneration starting in your 30s and 40s, what role anti-amyloid drugs actually play and who should and shouldn't be on them, and why programmable microglia and the gut-immune-brain connection may represent the next frontier in preventing the disease entirely. Dr. Jonathan Fellows is a neurologist with more than 25 years of clinical experience and serves as the Director of the Alzheimer's Disease and Memory Disorder Center at the Michigan Institute for Neurological Disorders, part of Corewell Health in Farmington Hills, Michigan, the largest private practice neurology group in the state. His interest in disease-modifying approaches traces back to the early days of multiple sclerosis treatment in the 1990s, where he saw firsthand how such therapies could change a patient's trajectory — an experience that shapes how he approaches Alzheimer's today. His practice integrates amyloid PET imaging, Centiloid scoring, blood-based biomarkers including P-tau 217, APOE genotyping, and structured lifestyle intervention, with metabolic health as one of the most powerful and underutilized levers for delaying cognitive decline. 00:00 - Introduction 00:39 - Brain Defenders: A New Way to Think About Brain Health 02:59 - Welcoming Dr. Jonathan Fellows 03:51 - Why Neurology School Doesn't Teach Prevention 05:27 - Inside the Michigan Institute for Neurological Disorders 07:44 - Starting the Conversation When a Family Gets the Alzheimer's Diagnosis 08:00 - Apraxia and the Real Warning Signs of Cognitive Decline 09:00 - Why Amyloid Alone Doesn't Equal an Alzheimer's Diagnosis 09:55 - The Centiloid Score: Measuring Amyloid in the Brain 11:21 - Blood-Based Biomarkers and the Rise of P-tau 217 13:19 - Elevated P-tau 217 at 40: A Wake-Up Call You Can't Ignore 13:32 - Habits in Your 30s and 40s vs. Disease in Your 60s and 70s 16:53 - 40 Hz Light Therapy and Cognitive Decline 18:53 - Why Not Every Amyloid-Positive Patient Should Get Anti-Amyloid Drugs 21:00 - Alzheimer's Drug Therapy Today vs. Where MS Treatment Stood in the 90s 23:59 - Why Early and Presymptomatic Detection Matters 25:21 - Will Anti-Amyloid Drugs Be Pushed to Presymptomatic Patients? 25:39 - What We Know for a Fact About Lifestyle and Disease Progression 26:27 - A Real Patient Case: When to Say No to Anti-Amyloid Drugs 28:30 - APOE Explained: The Gene That Changes Your Alzheimer's Risk 31:49 - 3X4 Genetics: Your DNA Isn't a Verdict 33:47 - How Exercise Can Offset APOE4 Risk 34:10 - APOE4 Is Not Deterministic — and Saying Otherwise Is Malpractice 34:51 - Down Syndrome, Presenilin, and the Truly Deterministic Cases 35:42 - ARIA Risk and Why Europe Restricts Anti-Amyloid Drugs for APOE4 Carriers 38:00 - Where Anti-Amyloid Drugs Still Fit in Treatment 39:14 - Current Clinical Trials at the Michigan Institute 39:49 - Programmable Microglia: The Brain's Immune System Explained 41:01 - Good Twin, Bad Twin: How Microglia Switch From Protector to Threat 42:09 - Beta-Amyloid as an Antimicrobial Defender? Rethinking the Enemy Narrative 42:49 - Insulin Resistance and the Brain-Metabolism Connection 43:41 - The Diabetes Epidemic Hiding in Plain Sight 43:58 - The Rainbow Lunchbox: A Preschooler Who Got It Wrong and Right 44:49 - Why a Third of Americans Are Pre-Diabetic and Don't Know It 46:30 - Closing Thoughts ___________________________ Instagram: / davidperlmutter Website: https://www.drperlmutter.com/ Subscribe to our channel: / @davidperlmuttermd