From the brains behind brains on, this is The Moment of Um.

Moment of Um comes to you from APM Studios. I'm Molly Bloom.

Um.

Why don't we have any thirstquenching beverages in the fridge?

I know I brought in some sparkling water the other day.

I hope Sandin hasn't been using it in his bathtub again.

He says he likes how the bubbles tickle.

Anyway, I just ate a big handful of dill pickle-flavored potato chips, and boy,

those things were salty. Delicious,

but salty. And now I really need to wet my whistle. See, can't whistle. Too parched. It always

feels like I'm about to shrivel up from dehydration when I eat a lot of salty snacks.

I wonder why that is.

My friend Kia was curious, too.

Why do salty foods make us thirsty?

I think we need a doctor's help for this one.

Music It's a really good question to ask, because to me it highlights something that's really important about medicine and science.

My name is Kavejoda. I'm a gastroenterologist. That's the kind of doctor who specializes in the organs of digestion in your body. Beliefs and thoughts that we have in medicine and science shouldn't be static things, which means they shouldn't stay the same forever. Science is a dynamic process, and that means it's changing.

It's constantly changing. So our thoughts and our beliefs on things in science and medicine can

change. As evidence changes, as our technology changes, so should our belief in some of the

things about science. So this is one of those instances where we have to have an open mind.

The traditional thought, when I was younger and taught about this, and when I think for even

maybe 100 years before that, people always assumed that you got thirsty after you had salt

...