Neurologist and bestselling author Dr. David Perlmutter returns to the Be Well by Kelly podcast to discuss the groundbreaking science behind his new book and why everything we thought we knew about Alzheimer's disease may be changing.
If you have ever worried about your brain health as you age, this is one of the most important conversations I have had on this podcast.
Meet Dr. David Perlmutter
Dr. David Perlmutter is a board-certified neurologist, Fellow of the American College of Nutrition, and one of the most influential voices at the intersection of neurology, nutrition, and lifestyle medicine. He is the number one New York Times bestselling author of Grain Brain, Brain Maker, and Drop Acid, books that have fundamentally shifted how millions of people think about diet and brain health.
His work has been featured in The New York Times, CNN, Fox News, and the Today show, and he has spent his career doing something rare in medicine: translating complex, emerging science into practical guidance that everyday people can actually use.
His newest book, Brain Defenders, is his most important work yet. It introduces readers to the emerging science of microglia, the brain's most critical immune cells, and makes a compelling case for why protecting these cells through lifestyle choices may be the most powerful thing we can do for our long-term cognitive health.
The Science Behind Alzheimer's
For decades the dominant theory of Alzheimer's disease has centered on amyloid plaques, abnormal protein deposits that build up in the brain. Billions of dollars and decades of pharmaceutical research have gone into targeting those plaques with limited success.
Dr. Perlmutter challenges that framework with a growing body of evidence suggesting that Alzheimer's is fundamentally a disease of chronic inflammation and metabolic dysfunction. At the center of this emerging science are microglia, the brain's resident immune cells that most people have never heard of but that may be the most important cells in the brain when it comes to long-term cognitive protection.
The gut-brain connection is equally central to this story. An imbalanced microbiome drives systemic inflammation that crosses the blood-brain barrier and activates microglia in harmful ways. What happens in your gut is directly shaping what happens in your brain, and the lifestyle habits that support one support the other in ways science is only beginning to fully understand.
This is not a fringe theory. It is where the research is pointing and it changes everything about how we think about prevention.
What You Will Learn in This Episode
This conversation is one of the most practically useful episodes I have recorded on brain health. Dr. Perlmutter connects the dots between the science and the daily habits that actually move the needle, and he does it in a way that is clear, compelling, and genuinely actionable.
We talk about why blood sugar balance may be the single most important factor in long-term cognitive health, and why some researchers now refer to Alzheimer's as Type 3 Diabetes. We go deep on the gut-brain axis, what the research shows about how your microbiome directly influences your risk of cognitive decline, and what you can do to support both. We discuss the foods with the strongest evidence for protecting brain function, including healthy fats, omega-3 fatty acids, polyphenol-rich foods, and fermented foods, and the dietary patterns most strongly associated with neuroinflammation and accelerated brain aging.
We also talk about the lifestyle factors with the most compelling evidence for Alzheimer's prevention, movement, sleep, stress management, and targeted supplementation, and why prevention is not a conversation that begins at 70. It begins with the choices you are making right now.
This episode reminded me that the habits we build around food, movement, sleep, stress, and gut health are not separate conversations. They are all part of the same story. And Brain Defenders makes that story impossible to ignore.
