Sara Lee Corp Chief Executive Officer Brenda Barnes said on Monday that she had suffered a stroke but was recuperating, in the company's first disclosure of the condition that prompted her to suddenly go on medical leave last month.

Sara Lee said it would provide an update on Barnes' health and her plans by August 12, when it will hold a conference call to discuss its full-year earnings.

I know there has been a lot of speculation on my condition, so I want to take the opportunity to provide some details, said Barnes.

I suffered a stroke a few weeks ago, and I am now in the process of recuperating.

Since May 14, Marcel Smits, Sara Lee's chief financial officer, has been working as interim CEO, while James Crown, its lead independent director, took on the role of chairman.

(Reporting by Phil Wahba; Editing by Lisa Von Ahn)