You're listening to an airwave media podcast. Your immune system is your body's primary defense. It's amazingly good at

identifying and destroying foreign invaders, but sometimes it makes mistakes, and these days our immune systems are making

mistakes more often.

Alerges, they're getting more prevalent, so you're seeing the rates of things like asthma, hay fever,

eczema, and food allergy rise globally, but they're also getting more severe.

So why does the immune system rear up against pollen or animal fur?

And why is the prevalence of allergies on the rise?

This is common and what we might do about it. Grab some tissues because this episode is allergy reason. The world can be a messy place.

The world can be a messy place.

Invisible Airborne Invaders lurk everywhere.

Even on a beautiful day, the air could be laced with things like automobile exhaust, dust, and pollen.

Hello, how's it going?

Good, how are you?

Let's go maybe just under these trees over here if that's okay?

And your skin, the largest organ in the body, bravely confronts it all.

But as our assistant producer Brian Edwards learned, we might want to resist our urge to scrub it down at the end of the day,

because our skin's microbiome is one of our immune systems first lines of defense.

I'm James Hamblin. I am a preventive medicine physician and a lecturer in public health at Yale.

Dr. Hamblin is the author of Clean, The New Science of Skin.

Brian met him in Brooklyn.

So we are sitting in Prospect Park right now.

It's very beautiful, but I will admit it's a little hot out.

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