When Oprah Winfrey reportedly acquired a 10 percent stake in Weight Watchers International, its stock jumped by more than 100 percent. (Jason Merritt/Getty Images)

Oprah Winfrey has found billionaire success in national broadcasting, publishing and as the godmother of the inspiration industry.

With her investment in Weight Watchers, she’s bestowed her starpower on a struggling brand.

And on top of that, she’s overcome a lifelong struggle with her weight to lose 40 pounds on the program. As her weight goes down, the company’s share price goes up.

Weight Watchers promotes a lifestyle and behavior program through weekly meetings and its subscriptions. When Winfrey paid $43 million in October 2015 for a 10 percent stake, the company was struggling to hold on to subscribers as people turned to fitness and dieting apps and relied more on gadgets like Fitbit.

Early this year, investors caught her tweets, TV interviews and commercials just as the traditional January skinny season took off. Weight Watchers shares have exploded since Jan. 1, rising 26 percent at Tuesday’s market close. They rose another 36 percent in early trading Wednesday after the company announced it had beaten analyst expectations with a fourth-quarter profit of $13.3 million.

(Victoria Walker,Julio Negron/The Washington Post)

“There is a big halo from her involvement on the brand,” said John Tomlinson, head of consumer research at M Science, a ­research analytics firm. “No question.”

In the fourth quarter, the company also issued a better-than-expected profit forecast and added subscribers.

The actress/filmmaker/philanthropist/television personality’s ups and downs and her exercise regimen — she tries to walk 10,000 steps per day — have been closely followed over the years. When she bought shares in ailing Weight Watchers in 2015, the price rocketed 100 percent.

“The impact of having a strategic marketing relationship with Oprah is not just a one-and-done deal,” said Alex Fuhrman, an analyst with Craig-Hallum Capital Group. “The fact that Oprah has had tremendous success personally on the program is very helpful. The company had a nice bounce in the 2016 diet season as a result of its relationship with Oprah.”

Winfrey, it seems, is unstoppable. What’s next? The presidency?

She demurs, but that has not silenced the chatter. In fact, one brief mention of the possibility created a national conversation.

David M. Rubenstein, co-founder of the Carlyle Group, brought up the idea when he interviewed Winfrey on “Peer to Peer Conversations,” his Bloomberg TV show.

With President Trump, he said, the American public elected “a media figure. Have you ever thought, given the popularity you have, that you could actually run for president and be elected?”

Trump’s victory apparently had gotten her thinking.

“I thought, oh, gee, I don’t have the experience, I don’t know enough,” she said. “And now I’m thinking . . . oh.”

The interview was taped after Trump was elected. Bloomberg premiered the Winfrey interview this week.

She attributed the success of “The Oprah Winfrey Show” to listening. “My skill comes not from my interviewing ability,” she said. “My skill comes from my listening ability, and my skill comes from me knowing fundamentally inside myself that I am no different than the audience. So what gave me the power in the seat and the power with the microphone was I always saw myself as the surrogate for the audience.”

Winfrey said she is “one of the happiest rich people you are ever going to see.”

“I would say the word for me now is I’m content,” she told Rubenstein. “I’m not just relaxed, I am content, because I know a lot of rich people who are not happy. But I am not one of them.”

And then Rubenstein steered back to politics, with “final questions as we wrap up — as you consider whether you’re going to run for president . . . ”

“No,” Oprah stopped him, “that won’t be happening.”

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