As a plastic surgeon in Northern California, Dr Stephen Williams performs a lot of operations.

We tackle the full spectrum from head to toe, facelifts, blephroplasties, liposuction tummy tucks, and breast augmentation.

But one of his most in-demand treatments happens outside of the operating room.

Every month, around 150 patients each pay hundreds of dollars to get one of the most toxic substances on earth injected into their faces.

Markets go up and down, the economy is good or bad, but Botox is one of those things that people will

really really try not to cut back on. 20 years ago people were very quiet about

it like I don't want anyone to know but now it's part of what people see as self-care.

Botox is often touted as a cosmetic miracle drug.

A few injections can temporarily reduce wrinkles and stave off signs of aging.

Last year, there are more than 9 million procedures involving Botox or competing

injectable brands in the US alone. You can get Botox or competing injectable brands in the US alone.

You can get Botox treatments from a credential doctor like Stephen Williams, who happens to be

the President of the American Society of Plastic Surgeons, but you can also get them at medical spas and even dentist's offices.

And people are seeking them out much earlier in life than they used to.

I think we're seeing a generational shift in the patients. Boomers treat things once they've happened.

millennials are into prevention and they've taken a look at their boomer parents

and thought, I don't want to go there quite as fast.

And so they've done, it's actually got a slang word, baby boatocks.

For the Freakonomics Radio Network, this is the economics of everyday things. I'm Zachary Krakett. Today, Botox.

Before Botox was a lucrative business, it was a deadly toxin found in sausages.

Like all crazy things, the story starts back in the 1700s.

Again, that's Dr. Stephen Williams.

...