Oprah Winfrey said she was leaving the board of directors of Weight Watchers, a few months after going public that she was taking a weight-loss drug.

The entertainment mogul has been the most prominent spokesperson for Weight Watchers since joining its board of directors in 2015, helping it overcome competition from other weight loss companies while opening a broader conversation about obesity and diet.

Her endorsement of Weight Watchers (she said she lost 40 pounds using the company’s points system) convinced many others to sign up, analysts said.

The announcement sent Weight Watchers stock into a tailspin, with shares falling 25 percent in early trading Thursday.

The company said in a special presentation with the Securities and Exchange Commission on Wednesday that Ms. Winfrey had notified the president that she would not run for re-election in May, concluding a nearly nine-year term on the board.

“Your decision was not the result of any disagreement with the company on any matter related to the company’s operations, policies or practices,” Weight Watchers said in the filing.

Winfrey, who has been a dominant figure in the country’s conversations about weight and dieting for decades, revealed in December that she was taking a weight-loss medication.

“The fact that there is a medically approved prescription to control my weight and stay healthier throughout my life seems like a relief, a redemption, a gift, and not something to hide from and be ridiculed for once again,” she said. told People magazine.

in a statement From the company on Thursday, Ms. Winfrey said she planned to continue advising Weight Watchers CEO Sima Sistani on “elevating the conversation around recognizing obesity as a chronic condition.”

A representative for Ms. Winfrey had no additional comment.

The company said in the statement that Winfrey would donate the value of her Weight Watchers holdings to the National Museum of African American History and Culture in Washington in part to “eliminate any perceived conflict of interest surrounding her taking weight-loss medications.”

The company did not explain the conflict of interest, and a Weight Watchers spokeswoman did not immediately respond to a request for comment.

He owned about 1.13 million shares worth $6.34 million, according to a Securities and Exchange Commission filing on Jan. 1.

Winfrey has not specified what weight loss medication she was taking. In 2021, researchers found that semaglutide, a drug to treat diabetes, produced dramatic weight loss results among patients with obesity. Since then, demand has skyrocketed for new drugs such as Ozempic, Wegovy and Zepbound that can help people lose weight, in part by suppressing appetite.

The emergence of these types of drugs has posed a commercial challenge for diet plans like Weight Watchers. But the company is pivoting toward a business model based on its ability to obtain the limited supply of the highly sought-after weight-loss drugs.

Last year, Weight Watchers acquired Sequence, a subscription-based telehealth platform that offers, among other benefits, access to healthcare providers who can prescribe weight-loss medications, including Ozempic, for $106 million. (Users pay $99 a month, not including prescription drug costs.) The company also eliminated some of its in-person meeting offerings, a popular tool in its weight loss plans, inspiring some customers to organize their own support groups.

After an initial run following the Sequence acquisition, Weight Watchers stock has lost more than half its value this year.

Shares of the New York City-based company have been hurt due to “exacerbated concerns” around its growth and liquidity prospects, said Stephanie Davis, an analyst at Barclays.

“It’s still early in their story of shifting from being more of an in-person diet model to shifting to a digital health company,” Davis said in an interview, adding that “the transitions have a lot of risks.”