I’ve Scanned 200,000+ Brains... Weed Kills Blood Flow 5x Faster Than Alcohol

Dr. Matt Kaeberlein is a biologist of aging, the CEO of Optispan, and a co-founder of the Dog Aging Project. He is also the founding director of the University of Washington’s Healthy Aging and Longevity Research Institute and has published over 250 papers on longevity. In this conversation, he breaks down why direct-to-consumer longevity products deserve skepticism, what the data actually says about rapamycin and intermittent fasting, and which biomarkers and scans are worth your money. In this episode, we discuss: (1:58) Why Matt Kaeberlein Resigned From a Longevity Academy in 2024 (9:14) How to Spot Longevity Hype and Misleading Supplement Claims (16:31) Lifespan vs. Healthspan: Have We Really Slowed Aging? (22:01) Curing Cancer Adds 2.5 Years. Slowing Aging Could Add 20. (24:43) Should Aging Be Classified as a Disease? (30:59) The Hallmarks of Aging Explained (39:39) Is VO2 Max the Best Longevity Metric? (47:29) The Intermittent Fasting Myth: What Mouse Studies Show (51:38) What Is Rapamycin and Does It Slow Aging? (58:00) Inside the Dog Aging Project’s Rapamycin Trial (1:01:19) Does Matt Kaeberlein Recommend Rapamycin? (1:04:37) Protein Maxing and mTOR: Does More Protein Speed Aging? (1:11:54) Are Biological Age Tests Accurate? (1:19:49) The One Biological Age Clock He Trusts: LinAge2 (1:24:29) Best Longevity Spend: $100 vs. $1,000 a Month

Dr. Nathan Bryan is a nitric oxide biochemist and the Founder, Chairman, and CEO of Bryan Therapeutics, with over 25 years of research and 100+ peer-reviewed papers on how the body makes this molecule. He's the author of The Secret of Nitric Oxide: Bringing the Science to Life. In this conversation, he explains how everyday habits like mouthwash, fluoride toothpaste, and antacids can quietly shut down blood flow, why erectile dysfunction can be an early warning sign of heart disease, and the daily routine he follows to protect his own vascular health.

Dr. Catherine Salmon is a Professor of Psychology at the University of Redlands and an evolutionary psychologist who has spent over two decades studying erotic fiction, pornography, and female sexuality. She's the co-author of Warrior Lovers: Erotic Fiction, Evolution and Female Sexuality and The Secret Power of Middle Children, and her research explores what romance novels and porn — the private products billions of people consume — reveal about the evolved mating psychology of men and women. In this episode, we discuss:

TRIGGER WARNING: Discussions of suicide and depressionIf anyone watching is personally struggling, the 988 Suicide & Crisis Lifeline (call or text 988 in the US) is always available.

Christopher Gardner, PhD, is a nutrition scientist and Professor of Medicine at Stanford University, where he has led more than 20 large-scale randomized clinical trials comparing diets like keto, vegan, low-fat, and low-carb. He's the past chair of the American Heart Association's Nutrition Committee and the author of the upcoming book Food Sense, which argues there's far more scientific consensus about what to eat than the internet's diet wars would suggest. In this episode, we discuss: