updated 09/04/2012 AT 7:10 PM ET
•originally published 09/04/2012 AT 7:30 PM ET
“I let myself indulge in everything I wanted because it was the first time I was ever pregnant, and I wanted to enjoy it,” Simpson, 32, tells USA Today.
That included eating one of her faves, macaroni and cheese. But Simpson didn’t quite understand how the indulgence would affect her post-baby body. “I didn’t realize [the weight] didn’t all come off with the baby,” says Simpson.
She’s now given up many of those foods, however, while doing Weight Watchers as the company’s newest spokeswoman – she appears in the ads next week.