#357 ‒ A new era of longevity science: models of aging, human trials of rapamycin, biological clocks, promising compounds, and lifestyle interventions | Brian Kennedy, Ph.D.
Release Date: 07/21/2025
The Peter Attia Drive
Antonio Bianco is a world-renowned physician-scientist and expert in thyroid physiology and metabolism. In this episode, Antonio explores the complex biology of thyroid hormone production, conversion, and regulation—highlighting how deiodinase enzymes modulate hormone activity at the tissue level and why that matters for interpreting lab results. He discusses the shortcomings of relying solely on TSH as a marker of thyroid function, the ongoing debate around combination therapy with T3 and T4 versus standard T4 treatment, and how genetics, tissue sensitivity, and individual variability...
info_outlineThe Peter Attia Drive
In this “Ask Me Anything” (AMA) episode, Peter breaks down the science of dietary fiber, moving beyond the blanket advice to “eat more fiber” to uncover what it actually does in the body and where its benefits are truly supported by evidence. He explains how different types of fiber—soluble, insoluble, viscous, and fermentable—affect digestion, satiety, weight management, and glycemic control, and compares their impact to other, more potent metabolic tools. Peter also examines how certain fibers influence lipid metabolism and cardiovascular risk, evaluates the strength of...
info_outlineThe Peter Attia Drive
Sally Greenwald is an OB-GYN who specializes in women’s sexual health from a hormonal and physiologic perspective, with expertise spanning desire, arousal, pelvic floor function, contraception, and menopause care. In this episode, she explains why sexual health is a vital component of overall well-being, exploring topics such as the drivers of desire, the anatomy of sexual function, myths and realities around orgasm, and the role of hormones in perimenopause and menopause. She also covers vaginal and pelvic health, pain with sex, evidence-based therapies for low desire and arousal, how...
info_outlineThe Peter Attia Drive
In this special episode, Peter provides a comprehensive introduction to longevity, perfect for newcomers or those looking to refresh their knowledge. He lays out the foundational concepts of lifespan, healthspan, and the marginal decade. Additionally, Peter discusses the four main causes of death and their prevention, as well as detailing the five key strategies in his longevity toolkit to improve lifespan and healthspan. Detailed show notes provide links for deeper exploration of these topics, making it an ideal starting point for anyone interested in understanding and improving their...
info_outlineThe Peter Attia Drive
In this “Ask Me Anything” (AMA) episode, Peter revisits the “proven, promising, fuzzy, noise, nonsense” scale and applies it to a variety of popular topics. He begins with a refresher on what each category represents before classifying a range of interventions based on the strength of their supporting evidence. The conversation spans three main areas: drugs for geroprotection (including GLP-1 receptor agonists, SGLT2 inhibitors, methylene blue, and telomere-lengthening supplements), the use of low-dose aspirin for cardiovascular disease prevention, and strategies to improve muscle...
info_outlineThe Peter Attia Drive
Rhonda Patrick is a scientist, health educator, and host of the FoundMyFitness podcast whose work explores the intersection of nutrition, aging, and disease prevention. In this episode, Rhonda joins Peter for part two of his deep dive on protein, continuing last week’s discussion with David Allison and expanding the conversation to include creatine supplementation and sauna use. She discusses why the current RDA for protein is insufficient, how much more is needed to maintain muscle mass and prevent frailty, how activity level and aging influence protein requirements through mechanisms...
info_outlineThe Peter Attia Drive
David Allison is a world-renowned scientist and award-winning scientific writer who has spent more than two decades at the forefront of obesity research. In this episode, David joins for his third appearance on The Drive to bring clarity to one of the most contentious topics in modern nutrition—protein. He explores the historical pattern of demonizing macronutrients, the origins and limitations of the RDA for protein, and what the evidence really says about higher protein intake, muscle protein synthesis, and whether concerns about harm are supported by actual data. He also discusses the...
info_outlineThe Peter Attia Drive
In this special episode of The Drive, Peter addresses the recent headlines linking acetaminophen (Tylenol) use during pregnancy to autism in exposed children. Recognizing the confusion these claims have sparked among patients, listeners, and the broader public, Peter uses this episode to provide a framework for thinking critically about complex conditions and the research related to them. He highlights the dramatic rise in autism diagnoses over recent decades, noting that multifactorial conditions rarely have a single cause, and emphasizes the importance of resisting oversimplified...
info_outlineThe Peter Attia Drive
Joe Liemandt is a software entrepreneur turned education reformer who left Stanford in 1989 to found Trilogy, a highly profitable private software company, before pivoting to transforming K-12 learning. In this episode, Joe shares how he transitioned from leading a global software enterprise to becoming principal of Alpha School, where his focus is building a mastery-based, individualized education model that leverages AI as the missing infrastructure for large-scale change. He details the shortcomings of traditional K-12 education, explains how Alpha replaces conventional seat time with...
info_outlineThe Peter Attia Drive
In this special episode of The Drive, Peter hosts a strength and conditioning roundtable with three experts in the field—Gabrielle Lyon, Jeff Cavaliere, and Mike Boyle. Together they explore why maintaining muscle mass, strength, and power is essential for healthspan and longevity, and examine how resistance training supports metabolic resilience and injury prevention across the lifespan. The conversation covers practical strategies for getting started and staying consistent, the importance of a protein-centered diet tailored to age and activity level, and approaches to resistance...
info_outlineView the Show Notes Page for This Episode
Become a Member to Receive Exclusive Content
Sign Up to Receive Peter’s Weekly Newsletter
Brian Kennedy is a renowned biologist, leader in aging research, and director of the Center for Healthy Longevity at the National University of Singapore. In this episode, Brian shares insights from ongoing human aging studies, including clinical trials of rapamycin and how dosing strategies, timing, and exercise may influence outcomes. He presents two key models of aging—one as a linear accumulation of biological decline and the other as an exponential rise in mortality risk—and explains why traditional models of aging fall short. He also explains why most current aging biomarkers lack clinical utility and describes how his team is working to develop a more actionable biological clock. Additional topics include the potential of compounds like alpha-ketoglutarate, urolithin A, and NAD boosters, along with how lifestyle interventions—such as VO2 max training, strength building, and the use of GLP-1 and SGLT2 drugs—may contribute to longer, healthier lives.
We discuss:
- Brian’s journey from the Buck Institute to Singapore, and the global evolution of aging research [2:45];
- Rethinking the biology of aging: why models like the hallmarks of aging fall short [9:45];
- How inflammation and mTOR signaling may play a central, causal role in aging [14:15];
- The biological role of mTOR in aging, and the potential of rapamycin to slow aging and enhance immune resilience [17:30];
- Aging as a linear decline in resilience overlaid with non-linear health fluctuations [22:30];
- Speculating on the future of longevity: slowing biological aging through noise reduction and reprogramming [33:30];
- Evaluating the role of the epigenome in aging, and the limits of methylation clocks [39:00];
- Balancing the quest for immortality with the urgent need to improve late-life healthspan [43:00];
- Comparing the big 4 chronic diseases: which are the most inevitable and modifiable? [47:15];
- Exploring potential benefits of rapamycin: how Brian is testing this and other interventions in humans [51:45];
- Testing alpha-ketoglutarate (AKG) for healthspan benefits in aging [1:01:45];
- Exploring urolithin A’s potential to enhance mitochondrial health, reduce frailty, and slow aging [1:05:30];
- The potential of sublingual NAD for longevity, and the combination of NAD and AKG for metabolic and exercise enhancement [1:09:00];
- Other interventions that may promote longevity: spermidine, 17𝛼-estradiol, HRT, and more [1:17:00];
- Biological aging clocks, clinical biomarkers, and a new path to proactive longevity care [1:23:15];
- Evaluating rapamycin, metformin, and GLP-1s for longevity in healthy individuals [1:32:15];
- Why muscle, strength, and fitness are the strongest predictors of healthspan [1:37:30];
- Why combining too many longevity interventions may backfire [1:39:30];
- How increased funding and AI integration could accelerate breakthroughs in aging research [1:41:45];
- The research Brian is most excited about, and the need to balance innovation with safety in longevity clinics [1:47:00];
- Peter’s reflections on emerging interventions and the promise of combining proven aging compounds [1:54:00]; and
- More.
Connect With Peter on Twitter, Instagram, Facebook and YouTube