'The Talk' Co-Host Sheryl Underwood Lost 90 Lbs., Admits She Considered Gastric Bypass

Sheryl Underwood couldn't stop smiling on set of The Talk as the hosts filmed promos for season 13 — and it's because she has a lot to celebrate.

Not only will the show feature a new theme song and carnival look for the premiere, but the co-host, who's in her twelfth season of the show, has a brand new look herself, having dropped 90 lbs. in the last year and a half.

Underwood, 58, remembers getting bad news from her doctor when her weight was hovering between 230 lbs. and 250 lbs. "My lab work: diabetic, pre-diabetic, hypertension, all the things that you hear, especially with women," she tells PEOPLE exclusively of her wake-up call. "I really wanted to get ahead of it."

Courtesy The Talk

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The 5'2" comedian had already begun taking Metamucil daily to help clean out her gut and give her digestive tract a fresh start, but she had also been exploring more drastic weight loss options — in secret.

Sonja Flemming/CBS

"I was going to have to have a surgery," Underwood shares through tears. "And when you do it, you have to go through the psychiatrist. You have to go through the dietician. But because I worked with the dietician, I lost weight. I didn't lose a significant amount, but I lost to a point where the insurance was not going to pay for it. Then when I was going to get the colonoscopy — I go get my colon looked at every year, but I went and got the endoscopy too — that's when my other doctor said, 'I got something I want you to try, and if it doesn't work, then we have to go [to gastric bypass surgery].'"

That "something" was Wegovy, an injection Underwood began taking weekly to help suppress her appetite and jump start her weight loss program.

Ron P. Jaffe/CBS

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"Obesity is one of the greatest risk factors for a myriad of cancers," Cedars Sinai Colon and Rectal Surgeon, Dr. Zuri A. Murrell, who treats Underwood, tells PEOPLE. "For many patients weight loss is very difficult. [Wegovy] offers another tool in our armamentarium to treat this 'disease.'  Wegovy targets areas in the brain that regulate hunger and food intake, thus decreasing the amount of food necessary to feel satiated. It also slows your gastro-intestinal motility so that you feel fuller. There is also some data that shows it stabilizes insulin levels, which is important for weight loss."

But the injection was only one component of her plan. Underwood, who helps take care of her disabled sister, knew she had to put in work, too. So she started to make lifestyle changes.

Courtesy The Talk

"Definitely getting more sleep," the Daytime Emmy Award winner says of the adjustments she's made. "Drinking more water. I'm eating fruit and vegetables that I never thought: green, leafy. I'm getting into eating blueberries and eating strawberries, and also getting more fiber in my diet with fiber supplements."

She's made such progress with portion control that she can even indulge in fast food occasionally.

"If I have a taste for McDonald's or Burger King or something like that, now I can eat the equivalent of less than a Happy Meal," Underwood reveals. "And I'm not starving."

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Courtesy The Talk

While Underwood started eating well, she also knew she had to get moving to burn calories.

"You want to move around," the actress adds. "But unfortunately, I'm in a career where you drive to work, you sit down and get your hair and makeup on. Sometimes I just get up and walk around, or I try to talk on the phone and walk around, or I'll do something while sitting in bed — I may do a little exercise, little stretching and things. I love the stationary bike because then I can listen to my music and be on the bike."

By reducing her food intake and increasing her exercise, Underwood has dropped four dress sizes and says she'd like to lose another 25 lbs. In the meantime, she continues to gets blood work done to track her progress.

Courtesy The Talk

"I feel amazing when I look at the lab work: normal, normal, normal, work on this," says Underwood, who hopes to be able to stop taking blood pressure medication soon. "And then I'll call my doctors: 'What do I need to work on?' "

Underwood says one of her biggest goals this season is to celebrate her birthday episode and show off her new figure in a special and meaningful way. "I've never worn a dress!" she says, adding that she will be walking in heels, too — no doubt with that same proud smile.

The Talk premieres on Sept. 12 on CBS.