Dr. Mary Claire Haver

I'll see what's going on here.

I wasn't really sure what was happening.

Though in our menopause group chat, which is probably 100 docs, and we have a WhatsApp that we kind of share information on, I had seen a few mentions of MCAS and its relation to endometriosis and other things.

And I was like, okay, I'll get to that.

Later, I'm still writing the book and busy, but it is really taken over the internet and like New York Times has written about it.

It's in all the major news magazines.

And then I saw you had posted on it as well.

So as the expert, I am so excited to dig into this topic.

But if people don't know who you are, you are a double board certified pediatrician and allergist immunologist, and you practice in Chicago.

You trained at Case Western, University of Illinois, and Wash U in St.

Louis.

And you have a ginormous following of 5 million followers.

And this is, I found you on the internet as well.

You are one of the most trusted voices in pediatrics and allergy and immunology.

And I am so excited to have you here with us today.

Okay, so what are mast cells?

What is histamine?

And what is happening right now on the internet?

You know, I learned, I knew histamine and its relation to allergies or the allergic response, but I did not realize until I started digging, like you, that there's a bigger connection here to multiple organ systems, kind of like estrogen.

So estrogen activates mast cells and progesterone calms them.