Your Cells Are Always Building A Whole New You

Over the past year, most of your body has replaced itself cell by cell. What can we learn from other animals’ dramatic feats of regeneration?

In the last year, you’ve basically replaced your body weight in new cells. So yes, it’s a new year, new you. To ring in 2026, we’re talking about starting anew, and drawing inspiration from tiny worms that embody the ultimate growth mindset—they can regrow a whole body from just a tiny piece of their tail. 

In this festive episode, Host Flora Lichtman talks with biologist Alejandro Sánchez Alvarado, a pioneer in the field of regeneration, about the science of regeneration and the biology lessons we can carry into the new year. 

Guest: Dr. Alejandro Sánchez Alvarado is a biologist and president and chief scientific officer of the Stowers Institute for Medical Research in Kansas City, Missouri.

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