Oprah Winfrey has purchased a 10% stake in diet-plan company Weight Watchers International in a bid to transform the corporation into an organization that promotes overall health and wellness.

The New York company said Winfrey would make a “substantial equity investment” in Weight Watchers and join its board of directors, in the process “bringing her insight to future products and programs.” She will also receive options “to acquire an additional 5% of the fully diluted shares.”

The move expands Winfrey’s media portfolio. She is also an owner of the OWN cable network — a media outlet that distributes programming based on her sensibilities — through a joint venture between her Harpo Productions and Discovery Communications. Through a partnership with Hearst Corp., Winfrey publishes O, a magazine with a similar mission. The inspirational figure rose to larger fame with the syndicated talk show she hosted for 25 seasons between 1986 and 2011.

“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,” said  Winfrey, in a prepared statement.  As part of the pact, Winfrey, whose efforts to maintain a healthy weight have long been scrutinized, will become a member of the Weight Watchers program.

“Through our conversations, it became clear that there is tremendous alignment between Oprah’s intention and our mission,” said Jim Chambers, Weight Watchers’ chief executive, in a statement. “We believe that her remarkable ability to connect and inspire people to realize their full potential is uniquely complementary to our powerful community, extraordinary coaches and proven approach.”