#398 ‒ AMA #86: GLP-1 RAs and muscle loss: new data, better questions, and how to preserve muscle during weight loss

#398 ‒ AMA #86: GLP-1 RAs and muscle loss: new data, better questions, and how to preserve muscle during weight loss

View the Show Notes Page for This Episode [https://peterattiamd.com/ama86/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed] Become a Member to Receive Exclusive Content [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed] Sign Up to Receive Peter's Weekly Newsletter [https://peterattiamd.com/newsletter/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed] In this "Ask Me Anything" (AMA) episode, Peter explores the effects of GLP-1 receptor agonists—including drugs such as Ozempic, Wegovy, and Zepbound—with a particular focus on their impact on muscle. He examines how much lean mass people actually lose during treatment and how those changes compare to weight loss achieved through other methods, while explaining why measurements of lean mass on DEXA scans can sometimes be misleading. Peter discusses the effects of these medications on bone mass, fracture risk, strength, and physical function, highlighting why functional outcomes may be more important than body composition metrics alone. He also explores how GLP-1–based therapies affect different fat depots throughout the body, identifies who may be most vulnerable to muscle loss, and outlines practical strategies for preserving muscle and bone health while using these medications. Finally, Peter reviews early insights into retatrutide, a next-generation weight-loss therapy, including what current evidence suggests about its effects on weight loss and muscle mass. If you're not a subscriber and are listening on a podcast player, you'll only be able to hear a preview of the AMA. If you're a subscriber, you can now listen to this full episode on your private RSS feed [https://peterattiamd.com/members/private-podcast-feed/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed]or our website at the AMA #86 show notes page [http://peterattiamd.com/ama86/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed]. If you are not a subscriber, you can learn more about the subscriber benefits here [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260629-pod-ama86&utm_content=260629-pod-ama86-podfeed]. We discuss: * The evolution of GLP-1 receptor agonists from diabetes drugs to breakthrough weight-loss therapies [1:45]; * Early concerns about lean mass loss with GLP-1 receptor agonists and the limitations of clinical trial data [3:45]; * How newer research has changed the understanding of lean mass loss on GLP-1 receptor agonists and why DEXA measurements can misrepresent muscle loss [6:15]; * Comparing lean mass loss across semaglutide, tirzepatide, and traditional weight-loss interventions [10:30]; * Comparing lean mass loss from GLP-1 receptor agonists with bariatric surgery, and whether these drugs cause muscle loss beyond normal expectations from substantial weight loss [13:15]; * The limited evidence regarding the timing of lean mass loss during GLP-1 therapy and the implications for exercise and nutrition strategies [16:00]; * Body composition changes after stopping GLP-1 receptor agonists: weight regain, fat regain, and lean mass recovery [17:45]; * Why lean mass measurements are an imperfect proxy for muscle health and function [21:45]; * The effects of GLP-1 receptor agonists on bone mineral density, fracture risk, and the importance of resistance training [23:00]; * Do GLP-1 receptor agonists directly cause muscle loss or simply mimic the effects of calorie restriction? [26:00]; * Why strength and physical function often improve despite lean mass loss on GLP-1 receptor agonists [28:00]; * Who is most at risk for lean mass loss during GLP-1–induced weight loss? [34:45]; * Intramuscular fat (IMAT), DEXA limitations, and the challenge of measuring true muscle loss [37:00]; * Preserving muscle while losing weight: resistance training, protein intake, and emerging research on preserving muscle during GLP-1–induced weight loss [39:00]; * Resistance-training principles for preserving lean mass during GLP-1–induced weight loss [43:45]; * Managing side effects and prioritizing protein intake while training on GLP-1 receptor agonists [46:15]; * Retatrutide: early evidence on its effects on weight loss, lean mass, and muscle function, as well as the limitations of the data being collected in ongoing clinical trials [48:00]; * The risks of using gray-market retatrutide before FDA approval [52:15]; * Key takeaways [54:30]; and * More. Connect With Peter on Twitter [https://twitter.com/PeterAttiaMD], Instagram [https://www.instagram.com/peterattiamd/], Facebook [https://www.facebook.com/peterattiamd/] and YouTube [https://www.youtube.com/channel/UC8kGsMa0LygSX9nkBcBH1Sg]

#397 ‒ Endometriosis and adenomyosis: diagnosis, fertility, reproductive aging, and emerging treatments | Renato Tomioka, M.D., Ph.D.

View the Show Notes Page for This Episode [https://peterattiamd.com/renatotomioka/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260622-pod-renatotomioka&utm_content=260622-pod-renatotomioka-podfeed] Become a Member to Receive Exclusive Content [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&renatotomioka%20=referral&utm_campaign=260622-pod-renatotomioka&utm_content=260622-pod-renatotomioka-podfeed] Sign Up to Receive Peter's Weekly Newsletter [https://peterattiamd.com/newsletter/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260622-pod-renatotomioka&utm_content=260622-pod-renatotomioka-podfeed] View our full terms of use [https://peterattiamd.com/terms-of-use/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260622-pod-renatotomioka&utm_content=260622-pod-renatotomioka-podfeed] Renato Tomioka is a leading expert in reproductive medicine and gynecologic surgery whose unique skills allow him to diagnose and treat some of the most impactful yet frequently overlooked conditions affecting women's health. In this episode, Renato explores endometriosis and adenomyosis, explaining what these conditions are, why they often go undiagnosed for years despite affecting millions of women worldwide, and how advances in MRI and specialized ultrasound are transforming diagnosis beyond traditional surgical laparoscopy. He discusses the decision-making process behind hormonal therapy versus surgery, how treatment strategies change when fertility preservation is a priority, and where IVF fits into the care pathway for women with endometriosis, adenomyosis, or age-related fertility decline. Renato also examines the profound effects of female age on egg quality and quantity, including the accelerating rise in chromosomal abnormalities after age 35, highlights common mistakes in both surgical and fertility management, and shares promising developments on the horizon for treating these conditions and preserving fertility. Follow Dr. Tomioka's work: Instagram: @dr.renatotomioka [https://www.instagram.com/dr.renatotomioka]; Website: Renato Tomioka, M.D., Ph.D. [https://www.renatotomioka.com] We discuss: * 0:00:00 - Intro * 0:00:11 - Endometriosis: definition, prevalence, infertility risk, and theories of disease development * 0:09:03 - The biology of endometriosis: estrogen dependence, progesterone resistance, and tumor-like growth mechanisms * 0:13:25 - Adenomyosis explained: how it differs from endometriosis, why it develops, and its impact on reproductive health * 0:18:52 - Recognizing endometriosis and adenomyosis: the "6 Ds" of endometriosis and key differences in clinical presentation * 0:22:09 - Uterine fibroids: classification, symptoms, and the importance of fibroid location for bleeding and fertility * 0:24:09 - Understanding endometriosis pain: lesion-driven pain, nerve involvement, central sensitization, and the importance of early treatment * 0:28:26 - Endometriosis in young women: rising prevalence, delayed diagnosis, and barriers to care * 0:33:11 - Modern diagnosis of endometriosis: specialized ultrasound, MRI, and the decline of diagnostic laparoscopy * 0:45:52 - Clinical case example #1: Managing endometriosis in a young woman seeking pain relief while preserving future fertility * 0:54:10 - Clinical case example #2: Comparing treatment strategies for symptom control versus fertility * 1:01:24 - Endometriosis and fertility: the roles of age, embryo quality, IVF, and surgery * 1:11:50 - Clinical case example #3: Managing adenomyosis after failed IVF transfers to improve implantation and pregnancy outcomes * 1:20:51 - The funding gap in endometriosis research: disease burden, economic impact, and growing awareness * 1:22:01 - Clinical case example #4: Surgical decision-making in endometriosis—balancing pain relief, fertility preservation, and common treatment pitfalls * 1:27:43 - Common misconceptions about fertility: maternal age, embryo aneuploidy, the inefficiency of human reproduction, and the limits of IVF * 1:34:23 - Elective egg freezing: timing, success rates, the fertility funnel, and the tradeoffs of fertility preservation * 1:45:49 - Emerging fertility technologies: mitochondrial replacement, ovarian tissue preservation, stem-cell-derived eggs, and current limitations * 1:55:10 - The future of endometriosis treatment: new guidelines, biologic therapies, and unanswered questions about IVF * 1:58:30 - Why earlier diagnosis matters: reducing years of suffering from endometriosis and adenomyosis Connect With Peter on Twitter [https://twitter.com/PeterAttiaMD], Instagram [https://www.instagram.com/peterattiamd/], Facebook [https://www.facebook.com/peterattiamd/] and YouTube [https://www.youtube.com/channel/UC8kGsMa0LygSX9nkBcBH1Sg]

#396 ‒ Breast cancer screening: understanding risk, deciding when to start and how often to screen, and choosing the right imaging strategy

View the Show Notes Page for This Episode [https://peterattiamd.com/breastcancerscreening/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260601-pod-breastcancerscreening&utm_content=260601-pod-breastcancerscreening-podfeed] Become a Member to Receive Exclusive Content [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&breastcancerscreening=referral&utm_campaign=260601-pod-breastcancerscreening&utm_content=260601-pod-sleeppharmacology-podfeed] Sign Up to Receive Peter's Weekly Newsletter [https://peterattiamd.com/newsletter/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260601-pod-breastcancerscreening&utm_content=260601-pod-breastcancerscreening-podfeed] In this episode, Peter explores the critical topic of breast cancer screening, examining why thousands of women continue to die from breast cancer each year despite the availability of effective screening tools. He explains the strengths and limitations of current screening strategies, reviews the recommendations from major medical organizations, and discusses why screening guidance can often seem confusing or contradictory. Peter outlines a practical framework for understanding breast cancer risk and personalizing screening decisions, including when to begin screening, how frequently to screen, and which imaging modalities may be most appropriate based on an individual's risk profile. Throughout the episode, he emphasizes that while population-based guidelines provide an important foundation, optimizing outcomes requires a more personalized approach aimed at helping women make informed screening decisions that can improve the chances of early detection and successful treatment. We discuss: * Why women still die from breast cancer: the benefits of screening, the problem of under-screening, and the need for risk-based screening strategies [1:45]; * Current screening recommendations, why they differ between organizations, and the importance of personalized screening decisions [6:30]; * A framework for personalizing screening [8:45]; * Assessing baseline breast cancer risk: genetics, family history, breast density, lifestyle factors, and the role of risk calculators in personalized screening [9:30]; * Balancing cancer detection and false positives: how breast cancer risk influences screening intensity and imaging choices [17:45]; * Mammography as the foundation of breast cancer screening: detecting ductal carcinoma in situ (DCIS) and the advantages of 3D versus 2D mammography [21:00]; * MRI for high-risk women: the benefits of supplemental screening, abbreviated MRI, and the emerging role of contrast-enhanced mammography [23:00]; * The role of ultrasound: supplemental cancer detection, diagnostic evaluation, and limitations compared with mammography and MRI [26:00]; * Choosing the right breast cancer screening strategy: imaging modality selection, screening hierarchies, and the importance of imaging center quality [28:00]; * How often should you screen for breast cancer? [30:15]; * At what age should you start screening? [37:30]; * Breast cancer in younger women: aggressive tumor biology, BRCA-related risk, breast density, and individualized decisions about when to begin screening [41:45]; * Inflammatory breast cancer, the limitations of screening mammography for symptomatic disease, and the importance of promptly evaluating new breast symptoms in both women and men [44:45]; * From risk assessment to personalized screening: a practical framework for reducing breast cancer mortality through earlier and more effective detection [46:30]; and * More. Connect With Peter on Twitter [https://twitter.com/PeterAttiaMD], Instagram [https://www.instagram.com/peterattiamd/], Facebook [https://www.facebook.com/peterattiamd/] and YouTube [https://www.youtube.com/channel/UC8kGsMa0LygSX9nkBcBH1Sg]

#395 - Brain lipidology: understanding APOE, cholesterol homeostasis, Alzheimer's disease risk, and the effects of lipid-lowering therapies on brain health | Tom Dayspring, M.D.

View the Show Notes Page for This Episode [https://peterattiamd.com/tomdayspring8/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260608-pod-tomdayspring8&utm_content=260608-pod-tomdayspring8-podfeed] Become a Member to Receive Exclusive Content [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&tomdayspring8%20=referral&utm_campaign=260126-pod-lisamosconi&utm_content=260608-pod-tomdayspring8-podfeed] Sign Up to Receive Peter's Weekly Newsletter [https://peterattiamd.com/newsletter/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260608-pod-tomdayspring8&utm_content=260608-pod-tomdayspring8-podfeed] Tom Dayspring is a world-renowned lipidologist and one of the most thoughtful teachers in the field of lipid metabolism. In this episode, Tom returns to The Drive for a deep dive into the relationship between lipids and brain health, beginning with the fundamentals of cholesterol transport before exploring why the brain's cholesterol system operates almost entirely independently from the rest of the body. Tom examines the roles of apoB, apoA-I, and especially apoE in cholesterol homeostasis, discusses how APOE genotype influences Alzheimer's disease risk, and unpacks the complex links between cholesterol metabolism, amyloid, and tau pathology. He also reviews what is currently known—and still uncertain—about the effects of statins, ezetimibe, omega-3 fatty acids, and emerging CETP inhibitors on brain health and neurodegenerative disease risk. Although highly technical, this conversation provides an essential framework for understanding the nuanced relationship between lipid-lowering therapies, cardiovascular disease prevention, and neurodegenerative diseases in an area often clouded by misinformation. We discuss: * The fundamentals of cholesterol transport in the body, and how peripheral cholesterol metabolism differs from cholesterol handling in the brain [2:45]; * How cholesterol is transported through plasma and stored within cells, and why lowering LDL cholesterol does not deplete the body or brain of cholesterol [11:45]; * How apoB particles drive atherosclerosis, why lowering lipids matters, and the factors that influence individual cardiovascular risk [20:00]; * How the brain produces and transports its own cholesterol using apoE lipoproteins independently of circulating cholesterol and apoB-containing lipoproteins [29:00]; * How apoB structure influences LDL receptor binding and LDL clearance [39:00]; * How neurons acquire cholesterol from apoE-containing lipoproteins and why desmosterol serves as a unique marker of cholesterol synthesis in the brain [41:45]; * The difference between the APOE gene and the apoE protein, the major APOE genotypes found in humans, and how APOE4 influences Alzheimer's disease risk [48:45]; * HDL function beyond cholesterol: immune function, protein cargo, and communication with the brain [53:30]; * How APOE4-associated defects in brain cholesterol transport may promote Alzheimer's disease: amyloid production, neuronal cholesterol homeostasis, and cholesterol clearance [58:00]; * Statins and brain health: reviewing the evidence of the potential impact of statins on cognition and Alzheimer's disease risk [1:09:00]; * Desmosterol and 24S-hydroxycholesterol as biomarkers of brain cholesterol metabolism and statin effects [1:17:15]; * Possible cognitive benefits of ezetimibe beyond lowering apoB [1:19:30]; * EPA, DHA, and the evidence for omega-3 fatty acids in brain health [1:23:15]; * Obicetrapib: an emerging CETP inhibitor with potential implications for both cardiovascular and brain health [1:31:00]; and * More. Connect With Peter on Twitter [https://twitter.com/PeterAttiaMD], Instagram [https://www.instagram.com/peterattiamd/], Facebook [https://www.facebook.com/peterattiamd/] and YouTube [https://www.youtube.com/channel/UC8kGsMa0LygSX9nkBcBH1Sg]

#394 ‒ Sleep pharmacology: the role of medications in healthy sleep, the promise of emerging therapies, and the evidence for common sleep supplements

View the Show Notes Page for This Episode [https://peterattiamd.com/sleeppharmacology/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260601-pod-sleeppharmacology&utm_content=260601-pod-genetictesting-podfeed] Become a Member to Receive Exclusive Content [https://peterattiamd.com/subscribe/?utm_source=podcast-feed&sleeppharmacology=referral&utm_campaign=260601-pod-sleeppharmacology&utm_content=260601-pod-sleeppharmacology-podfeed] Sign Up to Receive Peter's Weekly Newsletter [https://peterattiamd.com/newsletter/?utm_source=podcast-feed&utm_medium=referral&utm_campaign=260601-pod-sleeppharmacology&utm_content=260601-pod-sleeppharmacology-podfeed] In this episode, Peter dives into the pharmacology of sleep, exploring where sleep medications fit within the broader framework of achieving healthy, restorative sleep. He explains why sleep is a biological imperative, why behavioral and environmental interventions must remain the foundation of good sleep, and how medications can serve as useful tools when carefully matched to a person's specific sleep problem. Peter examines the major classes of prescription sleep medications, including how they work, their effects on sleep architecture, their duration of action, side effects, and risks of tolerance and dependence. He also discusses the dangers of using sleep drugs without a clear understanding of the underlying problem being treated, the role of medications as short-term bridges during periods of acute stress, pain, or anxiety, and the promise that newer drugs like DORAs may hold for Alzheimer's prevention in high-risk individuals. Finally, Peter reviews the evidence for select off-label medications and supplements commonly used for sleep. We discuss: * The biological foundations of sleep, the major drivers of sleep dysfunction, and the role sleep medications can play when appropriately matched to specific sleep problems [1:00]; * Sleep hygiene, circadian alignment, and the medical causes of insomnia: building the foundation for effective sleep treatment [7:15]; * Understanding insomnia: hyperarousal, CBT-I, paradoxical insomnia, and why different sleep problems require different treatments [12:45]; * The difference between sedation and physiologic sleep: sleep architecture, restorative sleep stages, and matching medications to specific sleep problems [17:00]; * Benzodiazepines for insomnia: mechanisms, effects on sleep architecture, and the risks of long-term use [18:45]; * Z-drugs for insomnia: how Ambien, Sonata, and Lunesta work, and the ongoing risks of sleep medications targeting GABA systems [23:00]; * Dual orexin receptor antagonists (DORAs) and the future of sleep medicine: orexin signaling, sleep architecture, and the emerging connection between sleep and Alzheimer's disease [27:15]; * Melatonin for circadian timing: how timing signals differ from sedatives in the treatment of sleep disorders [36:30]; * Trazodone for insomnia: preserving deep sleep while minimizing the risks of traditional sedative-hypnotics [42:00]; * First-generation antihistamines for sleep: short-term sedation, anticholinergic risks, and concerns about long-term cognitive health [44:00]; * Sleep supplements and the evidence behind them: glycine, magnesium, ashwagandha, phosphatidylserine, and more [45:45]; * Takeaways: supplement quality, individualized sleep treatment, and the importance of matching interventions to the biology of insomnia [52:00]; and * More. Connect With Peter on Twitter [https://twitter.com/PeterAttiaMD], Instagram [https://www.instagram.com/peterattiamd/], Facebook [https://www.facebook.com/peterattiamd/] and YouTube [https://www.youtube.com/channel/UC8kGsMa0LygSX9nkBcBH1Sg]