First Lady Michelle Obama joined with supermarket chains Wednesday as they promised to build stores in so-called “food deserts” that lack access to fresh groceries.

“The commitments that you all are making today have the potential to be a gamechanger for our kids and for our communities all across this country,” Obama said.

Participating retailers include Walmart, the country’s largest grocer, Brown’s Super Stores in Philadelphia, Walgreens and Calhoun Foods, which has locations in Alabama and Tennessee. According to the Partnership for a Healthier America, roughly 6.5 million children live more than a mile from a grocery store.

“When it comes to feeding families and enriching the life of a community, America’s supermarkets and grocery stores are among our nation’s greatest assets,” says Leslie G. Sarasin, president and chief executive officer of the Food Marketing Institute, a trade group.  “As evidenced by the commitment articulated today, the food retail industry continues and underscores its proud role in improving the access to healthier food for those in underserved areas.”

James Gavin III, chairman of the Parternship for a Healthier America, said, “Today we move past talking about statistics … and focus on steps toward a solution.”

Walmart alone has said it plans to open between 275 and 300 stores in underserved neighborhoods by 2016, serving a projected 800,000 people. The stores would also employ more than 40,000 people.

“Every American should be able to buy healthy food at a price they can afford,” Walmart Executive Vice President Leslie Dach said. “How can a parent serve their kids healthier meals when they can’t even get to a grocery story?”

Historically, grocery chains have been wary of opening in low-income areas because of high operating and building costs, according to a recent FMI study. But recently the industry has taken a second look at these markets as other locations become saturated.

“This is a business initiative,” Dach said. “It’s part of the growth plan.”