Media mogul Arianna Huffington announced Thursday she is stepping down as editor-in-chief of her namesake online news site to launch a health and wellness start-up.<br />"I thought HuffPost would be my last act," she tweeted.<br />"But I've decided to step down as HuffPost's editor-in-chief to run my new venture, Thrive Global."<br />She also thanked her employees of The Huffington Post and tweeted: "I'm filled with gratitude."
