They are the most-trusted profession in America (and with good reason). They are critical to patient outcomes (especially in primary care). Could the growing army of nurse practitioners be an answer to the doctor shortage? The data say yes but —  big surprise — doctors' associations say no.

In this live episode of "Tell Me Something I Don't Know," you'll learn about carcass balancing, teen sleeping, and brand naming. Joining Stephen J. Dubner as co-host is Alex Wagner (CBS This Morning Saturday); author A.J. Jacobs (It's All Relative) is the live fact-checker.