Continuous glucose monitoring didn’t start as sleek apps and tiny sensors — it began with chunky receivers, short wear times, and a lot of skepticism. In this episode, Dr. Jeremy Pettus and Dr. Steve Edelman sit down with Dexcom CEO and original sensor engineer Jake Leach to trace the evolution of CGM from those early “Tylenol-shaped” receivers and repurposed pagers to today’s G7 system and beyond.

They walk through the major turning points: abandoning long-term implants for subcutaneous sensors, proving that real-time CGM meaningfully improves time in range and safety, and pushing back against old-school thinking that insisted patients shouldn’t see their own data. From STS 3-Day to Seven Plus, G4, G5, G6, and now G7, Dr. Edelman, Dr. Pettus, and Jake Leach break down what each generation added — better accuracy, easier insertion, smartphone and cloud connectivity, and integration with pumps and AID systems.

Most importantly, Dr. Edelman, Dr. Pettus, and Dexcom CEO Jake Leach, focus on what’s coming next and what it means for people living with diabetes today: the 15 day Dexcom G7 sensor, Smart Basal insulin titration for people with type 2 diabetes, AI-powered food logging, and the upcoming G8 platform designed to measure multiple analytes (glucose plus ketones and more) — all while pushing toward broader access and affordability.

Key Topics:

• Early Dexcom Days & STS 3-Day: How Dexcom pivoted from implantable sensors to disposable subcutaneous CGMs and what the earliest systems were really like.
• Blinded vs Real-Time CGM: The ethics debate, safety implications, and studies proving real-time data improves time in range and reduces hypoglycemia.
• Seven Plus, G4 & G5: Major accuracy improvements, longer wear times, and the move to smartphone-based monitoring.
• G6 & Auto-Applicators: Eliminating mandatory calibrations and making sensor insertion faster and easier.
• G7 Wins & Growing Pains: Reduced size, faster warm-up, early reliability challenges, and how Dexcom addressed manufacturing and support issues.
• 15-Day Wear & Smart Basal: Extended wear life and CGM-guided basal insulin titration for type 2 diabetes.
• G8 & Multi-Analyte Sensing: A preview of Dexcom’s next-generation platform measuring glucose plus ketones and other markers.
• AI Food Logging & Smarter Care: Photo-based meal tracking and pairing nutrition data with glucose trends.
• Access & Affordability: Expanding CGM access globally and using data to reshape how diabetes care is delivered.

0:23 - Introduction & TCOYD’s 30th Anniversary
1:39 - Meet Jake Leach: 21 Years at Dexcom
3:08 - The Early Days: From Implantable Sensors to Patches
5:26 - The First Commercial CGM (STS 3-Day) & The "Pager" Receiver
8:35 - The Evolution to 7-Day Wear (Seven Plus)
10:15 - The Early Struggles with Insurance Coverage
12:32 - Why Unblinded Real-Time Data Changed Everything
16:36 - The G4 Era: Improved Accuracy & The "Share" Cradle
20:26 - G5: The Shift to Smartphone Connectivity
27:04 - Real Talk: Addressing G7 Connectivity & Sensor Failures
29:07 - Dexcom's "Unlimited Replacement" Policy for Failed Sensors
31:39 - CONFIRMED: The New 15-Day Sensor Launch
32:43 - "Smart Basal": A New Tool for Type 2 Diabetes
35:44 - G8 Reveal: Measuring Ketones, Lactate & Potassium
39:12 - New Feature: AI Smart Food Logging
41:22 - The Future of CGM: Pre-Diabetes & Heart Health
46:34 - Closing Thoughts

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