You know, sometimes it feels like we're already living in the future. After all, our smartphones,

they give us so much information. Whenever we want it, wherever we want it, instantly. Cars are

beginning to drive themselves. Our watches can track our heart rate, our step count, rings,

know how we sleep, and artificial intelligence,

I'm not even sure where to begin with that.

But it turns out humans have been into tracking and trying to better understand themselves for a long time now.

In fact, more than 500 years ago, just think about that, 500 years ago,

the famous artist, thinker, and inventor,

Leonardo da Vinci, he sketched something that looked very much like a basic step counter

or a pedometer, which honestly is not that different from how many of us use fitness

trackers today. But it turns out even back then, people were trying to figure out how to measure their own health.

People have long been fascinated with their own bodies and trying to quantify it in some way.

And these days, wearable technology does way more than count steps.

They can flag heart issues. They can detect

signs of high blood pressure. They can even pick up on hearing loss. They have quickly become

surprisingly powerful tools for preventive care. We feel almost a responsibility because we're

with you all the time to actually make you live a healthier life.

That's Dr. Sumbull Desai. She is Apple's VP of Health. She's a physician and a clinical

associate professor at Stanford Medicine. For years, she's been thinking about how to bring medicine

and wearable technology closer together. So I wanted to ask her, can these devices really help us catch health issues early?

Is there a fine line between information and panic or even drowning us in data?

How smart are these smart devices really at knowing when something's gone wrong, and does it actually

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