218 Beyond Lifespan: Why Healthspan is your Real Goal! with Dr. William Hsu

In Episode 218 OF GROWING OLDER LIVING YOUNGER, Dr. William Hsu, endocrinologist and Chief Medical Officer at L Nutra, joins Dr. Gillian Lockitch to explore the science behind fasting mimicking diets (FMD) and how they may lower biological age, fight chronic disease, and boost metabolic health. You’ll hear how simple lifestyle interventions, when structured and supported, can trigger the body’s natural repair systems—and why healthspan, not just lifespan, should be the goal of aging well. 

Dr. William Hsu is a Harvard-trained endocrinologist who spent 20 years at Harvard’s Joslin Diabetes Center before joining L-Nutra in 2019 as Chief Medical Officer. At L-Nutra, he leads clinical development and drives education around fasting and the Fasting Mimicking Diet. Previously, he served as Vice President at Joslin, leading international education and healthcare advisory efforts, helping to shape national diabetes care guidelines. Dr. Hsu’s research focuses on diabetes pathophysiology and digital health in chronic care. He earned degrees from Cornell and Mount Sinai, completed his Internal Medicine residency at Yale, and his Endocrinology fellowship at Harvard, where he was later an Assistant Professor.

  Episode Timeline:

0:00 – Introduction and Podcast Overview 
Host Dr. Gillian Lockitch introduces the theme for 2025: “Age is just a number.” She frames the episode around exploring strategies to extend healthspan—the years of life spent in good health—and invites listeners to book one-on-one sessions. 

2:12 – Meet Dr. William Hsu 
Gillian introduces her guest, Harvard-trained endocrinologist Dr. William Hsu. Formerly with the Joslin Diabetes Center, Dr. Hsu now leads clinical efforts at L- Nutra, pioneering fasting-mimicking nutrition science. 

4:50 – Lifestyle Change: More Than Just Willpower 
Dr. Hsu explains why lifestyle interventions often fail without structural support. He acknowledges the essential role of medications but stresses the need for more systemic, pragmatic solutions to improve public health. 

9:29 – Why Modern Life Challenges Healthy Living 
The conversation turns to the external forces—processed foods, advertising, time scarcity—that sabotage health. Dr. Hsu advocates for societal-level interventions and introduces fasting mimicking diets (FMD) as a practical tool. 

12:24 – What is a Fasting Mimicking Diet? 
Dr. Hsu defines the FMD as a plant-based meal plan that tricks the body into a fasting state while providing nourishment. He explains how FMD promotes autophagy, cellular renewal, and metabolic reset. 

28:23 – Clinical Trials: Reversing Biological Age 
Dr. Hsu cites a Nature Communications study where FMD reduced participants’ biological age by 2.5 years in just three cycles. He explains how biological age is measured and why it’s a more powerful indicator than the number on your birthday cake. 

31:53 – Can You Track Your Own Biological Age? 
Gillian and Dr. Hsu discuss current tools for measuring biological age and where the science is heading. Dr. Hsu shares how consumers can access FMD kits and programs in various global regions. 

33:14 – FMD and Diabetes Management 
Dr. Hsu shares compelling data showing how FMD can reduce visceral fat, insulin resistance, and blood sugar levels—attacking the root of type 2 diabetes and reducing reliance on medication. 

36:09 – El Nutra’s Comprehensive FMD Program 
Dr. Hsu describes a complete support system for FMD users, including medical oversight, apps, coaching, and lab tracking. The program is already in use in the U.S., UK, and Italy, and expanding. 

39:22 – Final Thoughts: Healing Through the Right Environment 
Dr. Hsu emphasizes the body’s innate ability to rejuvenate when supported by evidence-based nutrition like FMD. Gillian closes with a call to action: explore the tools discussed to take control of your aging journey. 

Action Steps: 

Check out posts in the Age is Just a Number 2025  A to Z Blogging Challenge

Schedule a one on one call with Dr. Gillian Lockitch. 

Join the Growing Older Living Younger  Community: https://www.facebook.com/groups/growingolderlivingyounger

Access Your Free E-book from Dr. Gillian Lockitch

Guide to Mind and Memory Boosting Strategies  

Learn about the work of Dr. William Hsu and L-Nutra

https://prolonfast.ca/

https://www.twitter.com/lnutraofficial/

https://www.facebook.com/LNutra/

https://www.linkedin.com/in/william-hsu-md/