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."
"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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"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."
Can it be done? YES! Will it take time, patience, action and discipline? YES! You get to choose how you want to feel, look and live! Whatever makes you happy it is your choice, take responsibility and don't create excuses! I chose to make a change and this is MY happiness and I I am not apologizing for my lifestyle! I loved me then but I love me more now, yes I said it I love me more now.....because of the freedom I have and new discoveries in my life! We are allowed to change when we want to and or stay the same. IT IS A PERSONAL CHOICE FOR EACH OF US!!! For myself, it's about constant change and growth, becoming better and staying true to my authentic self! Regardless if it's criticized and or celebrated, this is for me!!! Never be afraid to go after what makes you happy! Happy people will love you and unhappy people will judge you! YOU CAN INSPIRE PEOPLE BUT YOU CAN NOT CHANGE THEM! You can only change yourself! #noregrets #happy #love #life #driven #action
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."