Winfrey purchased 6.4 million shares of the company's stock
Credit: Gregg DeGuire/WireImage

Oprah Winfrey has plunked down $43.2 million for a 10 percent stake in Weight Watchers, the company announced in a filing with the Securities and Exchange Commission Monday.

As part of the agreement, Winfrey is joining the company’s nine-member board and will be allowing them to use her name, image and likeness to promote its services, subject to her approval. The $43 million sum translates to about 6.4 million shares.

“Weight Watchers has given me the tools to begin to make the lasting shift that I and so many of us who are struggling with weight have longed for,” Winfrey said in the statement. “I believe in the program so much I decided to invest in the company and partner in its evolution.”

The company’s stock jumped by as much as 75 percent in early trading after the announcement, though it’s down about 50 percent year-to-date and over the past year.

The investment move makes sense for Winfrey, 61, whose lifelong struggles with weight loss have been frequent topics on her show and in her magazine. She’s advocated for Weight Watchers before, and apparently inspired her friend Gayle King to start the program in recent weeks.