The peptide and GLP-1 conversation has reached a fever pitch. Growth-hormone-releasing peptides are being marketed as longevity tools, GLP-1s are being treated as a default rather than a last resort, and a wellness aesthetic of higher IGF-1, more muscle, and less fat is being sold as the route to a longer life. In this episode, I sit down with Dr Valter Longo, Professor of Gerontology at USC and Director of the USC Longevity Institute, to look at what the data actually says. Valter developed the Fasting-Mimicking Diet, has led foundational work on the growth hormone, IGF-1, insulin, and TOR axis across yeast, mice, and humans, and runs non-profit longevity foundation clinics in Europe and the US. He calls himself the anti-biohacker and makes the case using the totality of evidence rather than the loudest claim. What we cover: The peptide boom and why every line of evidence cuts the other way The body composition reality of GLP-1s after 3 to 4 years The optimal IGF-1 range and how to land there with food and timing The Fasting-Mimicking Diet across more than 47 clinical trials, including the biological-age reduction studies The Harvard plant-versus-animal protein data, properly read A grounded case against ketogenic patterns for longevity and what to eat instead If this conversation lands, a quick rating or review on Apple Podcasts or Spotify makes a real difference. To follow more of Dr Valter Longo's work, visit his website, find him on Instagram, and explore the work of the Create Cures Foundation, the Valter Longo Foundation, the Longevity Technology Institute, and the European Longevity Institute through his published research and his book The Longevity Diet. Intro (00:00) The Peptide Boom and What Is Actually Being Sold (00:01) GLP-1s: 92 Per Cent Drop-Out and the Body Composition Math (00:02) The Fasting-Mimicking Diet Reverses Western-Diet Damage (00:13) Snell, Ames, and Laron Dwarf Mice (00:18) The Laron Syndrome Cohort in Ecuador (00:24) Acromegaly and the Cost of High Growth Hormone (00:28) The Optimal IGF-1 Range: 120 to 160 ng/mL (00:50) Plant vs Animal Protein, Properly Read (00:57) The Anti-Keto Case from Okinawa to Loma Linda (01:08) Stanford Crohn's, Miami UC, and Rome Kidney Disease (01:22) Biological Age Reduction After Three FMD Cycles (01:25) FMD Safety Across More Than a Million Users (01:31) The Longevity Diet: Eat More, Eat Better (01:43) This episode is brought to you by: 38TERA Consider 38TERA's DMN prebiotic supplement a daily multivitamin for your gut. Formulated by yours truly and gastroenterologist Dr Will Bulsiewicz. Use code THEPROOF for a discount at checkout. 38Tera ships to the United States, Australia, and New Zealand. Pique Pique’s Nandaka combines fermented Pu’er tea, full-spectrum Reishi, ceremonial cacao, and L-theanine for calm, sustained energy without the coffee crash. Unlock 20% off and establish your powerful foundation for sustained well-being at Piquelife.com/SIMON. Pique ships within the U.S. and to Australia, Canada, and select EU countries. Function Health Take charge of your health with advanced blood testing and personalised insights. Function Health offers a practical way to track key health markers such as cholesterol, blood sugar, and more. Learn more and join at functionhealth.com/simonhill for a $25 credit toward your membership. Only available to those living in the United States. Function Health ships to 48 U.S. states, excluding Rhode Island, Hawai‘i, and Puerto Rico. Truemed Truemed helps qualified customers use pre-tax HSA or FSA dollars on health-related products like fitness, recovery, and sleep tools, often saving around 30% on average. Visit truemed.com/THEPROOF to see what qualifies. This is hands down the best way to make the most of your health dollars. IM8 With 92 nutrients, including Vitamin B12, Iodine, Selenium and Vitamin D, in highly absorbable forms, IM8 Daily Essentials is the perfect all-in-one daily multi-vitamin to ensure you meet your daily micronutrient needs. IM8 is offering an exclusive 10% off your first order with a free welcome kit when you enter the promo code SIMON at checkout on im8health.com. IM8 ships to 27 countries including the U.S., Canada, the U.K., Australia, and many regions across Europe, Asia, and South America. WHOOP WHOOP, the most advanced fitness and health wearable available. Your personalised fitness and health coach to recover faster, sleep better, and train smarter. Claim your first month free on join.whoop.com/simon. WHOOP ships to 56+ international markets, including the US, Canada, most of Europe, Australia, New Zealand, UAE, Singapore, and parts of Asia. Simon Hill, MSc, BSc (Hons) Creator of theproof.com Host of The Proof with Simon Hill Author of The Proof is in the Plants Subscribe & Connect: YouTube Apple Podcasts Spotify Instagram: @theproof Twitter: @theproof Facebook: The Proof with Simon Hill