"I don't think you could be prepared for the work that has to be done psychologically," Rosie Mercado tells PEOPLE

By Gabrielle Olya
Updated May 03, 2016 01:50 PM
Credit: Oscar Picazo

Rosie Mercado had reached a high weight of 410 lbs. when she was told by an airline employee that she needed to purchase a second seat to fit on the plane.

The embarrassing incident was an ‘aha’ moment for the mom-of-three, who decided she needed to lose weight, and successfully dropped to 300 lbs. through diet and exercise alone over the course of a year and a half.

Then, she reached a standstill, and even began putting on weight again.

“As soon as I hit 320, I was like, no I cannot go back to being 410,” Mercado, 36, tells PEOPLE. “I was going back and forth with my weight, and I saw a documentary on the [gastric] sleeve. I said, ‘You know what I’m going to do this. It’s the next part of my journey.’ ”

The curvy model said the real work came after having her surgery done.

“I don’t think you could be prepared for the work that has to be done psychologically,” she says, noting that she had to completely eliminate soda, dessert, pasta and rice from her diet, or else she felt extremely ill.

“Anything that bloats just completely went away,” she says. “You start really educating yourself on eating healthy, eating lean and eating really small portions. You go out with friends and you order an appetizer and eat half of that, and you sit there waiting for everyone else. It psychologically plays with your mind.”

It took Mercado a while to get used to her new lifestyle and her new body.

“You have to deal with being low-calorie, and deal with the adjustment to your body as you’re dropping weight,” she says. “You learn what you’re allowed to do and what you’re not allowed to do. If you do what you’re not allowed to do, you’re going to feel like crap.”

Choosing to get gastric sleeve surgery was a “tough decision,” says Mercado. “It’s not an easy walk. Surgery is just a tool. It’s not guaranteed success. Success comes from the discipline – it forces you to wake up and pay attention to what you’re eating. It’s a lifestyle.”

Mercado got the surgery to get healthy – not to be super thin.

“There’s no goal for me to be a size 6,” she says. “I just want to be healthy and fit. Being obese is putting your life at risk every single day.”

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Thanks to her surgery and dedication to a healthy lifestyle, Mercado lost over 200 lbs. – which led to a new problem. Mercado had 20 lbs. of excess skin on her stomach, which led to rashes, pain and general discomfort.

“I had to be in Spanx the entire time,” she says. “I couldn’t run without Spanx because of the weight of the skin. You lose all this weight, you’re excited, and then you take your clothes off and you have all this excess skin. New issues start coming up.”

So Mercado decided to get skin removal surgery, getting a full tummy tuck to reconstruct her abdomen.

“That has been by far the most painful journey of my entire life,” she says. “It was burning, aching, tubes coming everywhere.”

Even though it was a long and painful process, she has no regrets.

“I would do it all over again because I am able to wear clothes that I was never able to wear, I can run and I don’t feel the pulling of my skin, I’m not dealing with the skin rashes,” she says.

Now, Mercado has lost a total of 240 lbs., bringing her from a size 36 to a size 12/14.

“I’m not perfect, I’ve still got cellulite, but it’s a huge improvement to the problems I was dealing with,” she says. “I’m able to do so many more things. My confidence comes, not just from the way that I look, but from the freedom that I have.”

She remains committed to a healthy lifestyle to maintain her goal weight. Mercado goes to boot camp classes three days a week, and runs and walks three other days a week. She sticks to a diet of lean protein, vegetables and fish, and avoids sugar.

And she doesn’t really care if other people disapprove of her choices.

“I’ve already gotten slammed for losing weight,” says Mercado. “Everybody says, ‘You’re no longer plus size.’ If you compare size 12/14 to a size 36, I don’t look plus size, but I’m still plus size, I still have curves. At the end of the day, it’s your body and [you should do what] makes you feel better.”