Oprah Winfrey has parted ways with WeightWatchers after revealing her use of an unspecified weight loss medication as part of her wellness routine.

On Wednesday, WeightWatchers confirmed that Winfrey would not be standing for reelection on its board of directors in May, thus concluding her nine-year tenure with the company.

In a statement on WeightWatchers’ website, Winfrey said she planned to donate her shares in the company to the National Museum of African American History and Culture while remaining “a vocal advocate in advancing [the] conversation” around weight management.

“I look forward to continuing to advise and collaborate with WeightWatchers and CEO Sima Sistani in elevating the conversation around recognizing obesity as a chronic condition, working to reduce stigma, and advocating for health equity,” she said.

Thilo Semmelbauer, who is WeightWatchers’ chairman of the board, called Winfrey “an inspiring presence and passionate advocate” for all of the company’s members, adding: “What I know for sure, we will dearly miss her presence on the Board.”

Winfrey bought a 10% stake in WeightWatchers and joined its board in 2015. Since then, she’s been one of the company’s most prominent celebrity spokespeople and appeared in a number of ad campaigns. By 2017, she’d reportedly lost 42 pounds while on the program.

In December, however, Winfrey confirmed that she’d begun taking weight loss medication as a “maintenance tool” after consulting with her doctor.

“The fact that there’s a medically approved prescription for managing weight and staying healthier, in my lifetime, feels like relief, like redemption, like a gift, and not something to hide behind and once again be ridiculed for,” she told People. “I’m absolutely done with the shaming from other people and particularly myself.”

Winfrey notably did not specify which weight loss drug she’d taken, and WeightWatchers has recently begun evolving its program to account for those taking prescription medications as a method to shed weight.

Still, the entertainment mogul’s announcement drew a mixed response that reflected the ongoing discourse around Hollywood’s embrace of Ozempic, a diabetes treatment that manages blood sugar levels, for weight loss.

In recent years, stars like Chelsea Handler and Sharon Osborne have gone public about using Ozempic. But the drug’s skyrocketing popularity has reportedly led to a global shortage, meaning that many patients with Type 2 diabetes have been unable to access it.