She was born in Brooklyn, and later taken up in Westbury on Long Island to parents Seymour and Joan Bleck, a young Jewish couple. In 2004, Rosenfeld appointed chief executive of Frito-Lay, a division of PepsiCo, where she focused on promoting healthy products. Rosenfeld has worked for 25 years in the food industry. Rosenfeld is a member of the Economic Club of Chicago. October 2010, Forbes ranked Rosenfeld 2 on the 10 most powerful women.
