Jessica Simpson Katie weight

Jessica Simpson still knows how to make an entrance. The actress/singer/pitchwoman debuted her
newly svelte body on the premiere episode of "Katie," the talk show hosted by Katie Couric.

Simpson's appearance was something of a big deal. The new mom had taken some flake for her weight gain during her pregnancy. On "Katie," Simpson addressed the issue.

"I put on more baby weight than I was planning on," Simpson said. "It is definitely a challenge. I've had to stay focused on my diet, really concentrate on what I'm putting in my body. The tabloids try to put the pressure on you [but] I have to separate myself from the world's expectations. If I got caught up in what the world was saying, I wouldn't be here right now, being as phenomenal as I am."

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So, how much did Simpson lose? She said she lost more than 40 pounds, but declined to be any more specific. "It's not about the numbers," Simpson said. She did say that she is 10 pounds away from her pre-baby weight.

According to Simpson, much of her baby weight was water. “My doctors told me [my pregnancy weight] was a lot of water, and when my water broke… All the weight did not come out with the baby. I had to stay focused on my diet. I want to be as healthy as I can because I'm a mom now."

Simpson also showed off her first commercial for Weight Watchers. After watching it, Couric noted that the commercial focuses only on Simpson's face and not her body. "I didn't want the big body reveal moment -- it's not who I am," Simpson said. "Everyone has their own issues and I really wanted it to be about the spirit of Weight Watchers. I wanted to talk directly to people."