Get smart curated videos delivered to your inbox.   SUBSCRIBE
The Kid Should See This

How Old Is Your Body, Really?

Watch more with these video collections:

Have you ever heard the statement that the cells in your body are completely replaced every seven years? Is this true? In this beautifully illustrated episode of Skunk Bear, NPR’s Adam Cole explores how long our different body tissues and cell types last… brand new fingernails every six months, 2-7 years for the hair on our heads, new skeletal muscles every 15 years, and more. Come for the quick facts and stay for the poetry of what remains with us for all of our lives.

By the way, how did scientists determine all of these different lifespans? Read more at Skunk Bear’s Tumblr.

Pair this video with The Animal That Wouldn’t Die.

Learn more about how your body works here, including how wounds heal & how scars form, what happens when we breathe, how our nervous systems work, and how our hearts pump blood.

This Webby award-winning video collection exists to help teachers, librarians, and families spark kid wonder and curiosity. TKSST features smarter, more meaningful content than what's usually served up by YouTube's algorithms, and amplifies the creators who make that content.

Curated, kid-friendly, independently-published. Support this mission by becoming a sustaining member today.