Physician James Hamblin, staff writer for The Atlantic, explains what would happen if you stopped showering — and other fun facts from the emerging science of the skin microbiome. Plus: are some trees really immortal?
Physician James Hamblin, staff writer for The Atlantic, explains what would happen if you stopped showering — and other fun facts from the emerging science of the skin microbiome. Plus: are some trees really immortal?
Are some trees immortal? A new study says no by Grant Currin
Additional resources from James Hamblin: board-certified preventive medicine physician, staff writer at The Atlantic, and lecturer in public health policy at Yale University
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Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/what-if-you-stopped-showering-w-james-hamblin-and-are-some-trees-immortal
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about whether some trees really are immortal. Then, we’ll talk to physician James Hamblin to learn what would happen if you stopped showering — and other fun facts from the emerging science of the skin microbiome.
CODY: Let’s satisfy some curiosity.
I’ve got some news. Are you ready? Trees. Are not. Immortal. I know, kind of a letdown. But stay with me. Scientists weren’t sure whether trees actually age like you or I do. Now, a new paper is shedding some light on the question.
Most people know that Earth is home to some very old trees. So it wasn’t too hard to believe a study about tree lifespans that came out earlier this year. The researchers analyzed the genes of 600-year-old ginkgo trees and found that they were thriving with the vigor of trees that were just 20.
It’s a fascinating study! But it led some news outlets to get a little carried away with headlines like “Why the Gingko Biloba Tree Is Basically Immortal.” So another researcher published a paper later in the year arguing that, sorry, trees are very much mortal. But they age so slowly that it’s hard for humans to notice.
Old trees are OLD. The most senior live to be about five thousand years old. That means they were saplings about the time when humans invented writing. They were hundreds of years old when the Great Pyramid of Giza was built. How can anything possibly live so long?
For one thing, it helps that trees have a fairly simple body plan. Roots, trunk, branches, leaves. Keeping it simple makes recovering from damage a lot easier. For instance, if a tree loses a few branches in a storm, it’s not too tough for it to sprout a new limb and replace what was lost. If I lose a body part, I’m down a body part and a lot of blood. As the Twitter meme says: We are not the same.
Trees also use their own dead tissue as a building material. In older trees, the trunk could be 90 percent dead wood, giving the tree heft and height without requiring nutrients or maintenance.
These strategies mean that for some species, older trees actually have a better chance of survival than younger ones. But that doesn’t mean they’re immortal. In the end, stress and other symptoms of age build, from subtle aches and pains to life-ending physiological changes. In ginkgoes, for instance, the vascular tissue that transports water and nutrients up the trunk gets thinner with age. Time also depletes the supply of a tree’s growth hormone.
Scientists are still learning more about how trees age, but don’t hold your breath for a lot of definitive studies anytime soon. As you might imagine, these experiments take a very long time.
Over the course of your life, you'll spend about two full years just washing yourself. That’s a LOT of time. So that fact might make you wonder: what would happen if you just stopped showering? I mean, humans spent a pretty long time surviving without being squeaky clean. Is it really necessary for us to stay so sanitized? The answer...is actually kind of complicated, according to Dr. James Hamblin. He's a staff writer at The Atlantic, a lecturer at the Yale School of Public Health, and a specialist in preventive medicine — and, oh yeah: he actually did stop showering to see what would happen to his skin. (More on that in a few minutes.) He’s also the author of a new book called “Clean: The New Science of Skin,” which explains the surprising effects of our hygiene practices. It all has to do with the new science of the skin microbiome. Yes, I said “microbiome.” You’ve heard of the gut microbiome and the eye microbiome, and yes, researchers have recently started spending more time researching the skin microbiome. We asked James: what do we know about the skin microbiome, and what are the little microbes all over us actually doing for our skin?
[CLIP 4:00]
We definitely don’t have enough time on this podcast to dive into the whole history of skin care. But hopefully you at least understand that skin care and cleanliness is actually a lot more complicated than the idea that you need to shower every day. If you want to learn more, you can pick up James Hamblin’s newest book, “Clean: The New Science of Skin,” which we’ll put a link to in today’s show notes.
Let’s recap today’s takeaways
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CODY: Today’s first story was written by Grant Currin, and edited by Ashley Hamer, who’s the managing editor for Curiosity Daily.
ASHLEY: Today’s episode was produced and edited by Cody Gough.
CODY: Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!