New York CNN  —  Oprah Winfrey said on Thursday evening that she has long played a role in promoting unhealthy and unrealistic diets. “I want to acknowledge that I have been a steadfast participant in this diet culture,” she said during a live event broadcast on YouTube in partnership with WeightWatchers. “Through my platforms, through the magazine, through the talk show for 25 years and online. I’ve been a major contributor to it. I cannot tell you how many weight loss shows and makeovers I have done and they have been a staple since I’ve been working in television,” she said. Winfrey admitted that through her focus on weight, she “set a standard for people watching that I nor anybody else could uphold.” The three-hour live special, which also featured actresses Rebel Wilson, Amber Riley, WeightWatchers CEO Sima Sistani and a number of doctors and other expert voices, highlighted a shift away from diet culture for WeightWatchers and toward body acceptance and medical intervention with drugs like Ozempic. Sistani said during the special that the company acknowledges that weight loss isn’t strictly a matter of willpower and that diet culture and body shaming isn’t healthy. Winfrey told People Magazine in December that she has added a “weight-loss medication to her regimen” but didn’t specify which drug. Winfrey and WeightWatchers Winfrey left the board of WeightWatchers, ending a nearly decade-long stint as a director of the beleaguered company, in February. A reason wasn’t revealed, but a WeightWatchers regulatory statement said that her “decision was not the result of any disagreement” or “any matter relating to the company’s operations, policies or practices.” “Oprah is an inspiring presence and passionate advocate both for our members and for society at large, in elevating the conversation around weight health,” said Sistani, on a call with investors at the time. “While I and the rest of our directors will certainly miss her in our board meetings following the end of her current term, she remains a strong strategic voice and collaborator with WeightWatchers.” Winfrey also said she would be giving away her sizable stake in the company: She said in a statement that she’s donating all of her stock to National Museum of African American History and Culture. Winfrey’s exit was a year earlier than expected, with the media mogul in 2019 signing an extension until 2025. A WeightWatchers representative told CNN that “Oprah is a former board member of WeightWatchers and tonight the company is thrilled for her to be the moderator of this event,” when asked to clarify what role Winfrey currently plays at the company. WeightWatchers shares (WW) are down nearly 75% over the last 12 months, but soared more than 11% higher on Thursday, ahead of the live event hosted by Winfrey. The GLP-1 revolution WeightWatchers in December launched a new membership plan for members taking GLP-1 prescriptions drugs like Ozempic and Wegovy sometimes used for weight loss. The “WeightWatchers GLP-1 Program” gives WeightWatchers members on semaglutide medications access to doctors who can prescribe these medications, as well as daily nutrition plans, insurance coordination, and other weight loss support programs. The announcement came months after WeightWatchers made a $100 million-plus deal to buy Sequence, a telehealth business that offers virtual prescriptions to patients for these weight loss drugs where appropriate. “I will say that I was on the board at the time there were discussions about whether or not WeightWatchers would move into weight loss medications,” Winfrey said on Thursday. “And as someone who struggled on WeightWatchers, I said ‘you all better join them or you will be overrun.’ And so I was in support of the company buying Sequence and going into that whole avenue.” Analysts at Goldman Sachs project that 15 million adults in the US will be on these medications by 2031, or about 13% of all adults in the country — not including diabetic patients. Nathaniel Meyersohn and Jordan Valinsky contributed to this story.