Burt Reynolds' frail appearance during a rare, recent public event has prompted concerns about his health.

The 79-year old Hollywood icon appeared unusually thin during a promotional event for his upcoming memoir, "But Enough About Me," Fox News reports.

Reynold’s forthcoming book focuses on the actors and personalities he’s worked with over the course of his career.

“I got along great with 98 percent of them, and a few of them I didn’t like at all,” Reynolds told the Philly Inquirer. “When you write a book like this, you have to tell the whole thing, and there are days when everything isn’t wonderful and there were people who I thought were asses.”