Oprah on Weight Loss and Lifestyle Change: 'I'm Ready to Go Beyond the Scale'

By Julie Mazziotta

@julietmazz

12/02/2015 AT 10:00 AM EST

Oprah Winfrey isn’t shy about discussing her weight loss ups and downs – but this time the new part-owner of Weight Watchers is determined to make a permanent lifestyle change.

Winfrey, 61, talked about how she’s working to change her perspective on healthy eating in the January issue of O magazine, revealed exclusively to PEOPLE.

“I’ve wishy-washed with diets and exercise my whole life,” she says in the cover story, on newsstands Dec. 8. “Now I’m ready to go beyond the scale and declare a new way of being in the world.”

The former talk show host says she’s tried diets over and over again, only to get frustrated with them and fail.

Oprah Winfrey

Ruven Afanador

“I was fed up with my lose-and-gain-again routine,” Winfrey says. “I’d had enough of no-carb regimens. Some people can live without bread and pasta, but it just doesn’t make sense to me. All the times I tried to do so only made me crave them more.”

Which is why Weight Watchers was the perfect fit for the lifestyle guru.

“I wanted a plan for life, and here it was in the form of Weight Watchers. For me, this is not a diet. It’s a whole shift in perspective. So yes, for sure, I’m a bona fide convert.”

For the shoot, Winfrey dressed in athleisure, enjoying the comfort. “I could live in pajamas all day long.” The star says she practices yoga and meditation regularly.

Oprah Winfrey

In October, Winfrey purchased a 10 percent stake in the company for $43.2 million, which led Weight Watcher’s stock to jump 75 percent that day.

RELATED VIDEO: Oprah Reveals How Much Weight She’s Lost on Weight Watchers since August

And she proved that the program really works – by trying it herself. Winfrey showed up for an appearance on Stephen Colbert’s The Late Show at the end of October looking visibly slimmer, and later revealed on Ellen that she had dropped 15 lbs. since Aug. 12.

And in the new year, she says she hopes to keep that healthy energy going.

“Now repeat after me: Here’s to good health. To the new year. To simply (or not so simply) deciding to be happy. To finally getting motivated,” she says.

Oprah on Weight Loss and Lifestyle Change: "I"m Ready to Go Beyond the Scale"