This is fresh air, I am Terry Gross. We're going to talk about the hidden world inside our bodies,

the remarkable design of our organs, the messages contained in our body fluids,

and how things can turn foul when something goes wrong.

My guest, Dr. Jonathan Reissman, is an internist, pediatrician, and ER physician,

and the author of the new book, The Unseen Body.

Each chapter is about a specific body part or body fluid from his perspective as a doctor,

so there's chapters on the throat, heart, feces, genitals, liver, brain, skin, urine, blood, and so on.

It's fascinating material, but I want to acknowledge at the start that our conversation

will include discussion of body fluids and genitals, and I know that makes some people uncomfortable or squeamish.

I suspect Dr. Reissman will try to convince you that you needn't be squeamish about the complexity of the human body.

Before studying medicine, his passion was studying the natural world and ecology.

As a medical student, he found that exploring the body felt similar to exploring the outside world.

Each organ was a different creature with its own unique appearance and behaviors.

He's practiced medicine in remote and culturally unique regions of the world,

including the Arctic, Antarctica, high altitudes in Nepal, people living on the street in Calcutta and India,

and among the Aglala Sioux in South Dakota.

He currently works in several ERs in the Philadelphia area.

Dr. Jonathan Reissman, welcome to Fresh Air. It's a fascinating book.

I know you're fascinated by our insides, our organs, our body fluids.

It's part of what drew you to medicine, but many people are squeamish about looking even at a video of a chest cut open during surgery.

What do you think that the body can seem so revolting or upsetting?

Well, thanks so much for having me here today, Terry.

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