JIM LEHRER: And to our interview with the first lady. I spoke with her this afternoon at her office in the East Wing of the White House.
Mrs. Obama, welcome.

FIRST LADY MICHELLE OBAMA: Thank you. Thanks for having me.

JIM LEHRER: Why did you choose childhood obesity as your major project?

MICHELLE OBAMA: I think I connected with it as a mother because I remember so clearly life before the White House, and it was a life that most working parents are dealing with, where you're juggling jobs and trying to get kids to and from and you're trying to make life easier. You're eating out more and you're probably moving less because you're carpooling and you're sitting and kids are watching TV and as a result of this lifestyle, this busy, hectic lifestyle, my pediatrician pointed out some changes in my kids' body mass index that he just sort of checked us on. And I hadn't even thought about it - hadn't thought about our lifestyle. But the beauty of that situation, for me, was that I made some pretty minor changes over the period of months, and saw what the doctor said were pretty remarkable changes, that he usually didn't see in his practice, which is a predominantly African-American, urban practice.

So he was pretty floored by how quickly you could turn the tide on this issue with - by just removing juices from lunchboxes and cooking a little bit more, maybe one or two more meals, turning the TV off a little bit more, limiting desserts to the weekends. I mean these were really not major lifestyle overhauls. So when I came here, I thought, if it can be that simple, it's all about lack of information and lack of focus on the issue. So I wanted to use the first lady spotlight to shine the light on this issue for many families that are struggling with this issue.

JIM LEHRER: Did you consider other causes? Something more related, say, or directly related to the recession, unemployment, that sort of thing?

MICHELLE OBAMA: Well, there have been several issues that I've developed over the course of my first year. Children's health and nutrition is one; with planting the garden - that was really sort of laying the foundation and using that year to learn more. But I have and will continue to focus on supporting our military families; national service will continue to be something that I'm promoting around the country.

So I'm still multitasking. It's really with childhood obesity that we saw an opportunity to really launch a major initiative that we thought could move the ball. So a lot of this effort results from the belief that this is something that we can do something about.