04/19/2010 at 01:00 AM EDT
She scored an Oscar for her career-defining role in Dreamgirls
, collected a Grammy for her debut R&B album and even went Manolo a Manolo with Sarah Jessica Parker
in the hit Sex and the City
movie. But lately fans are having a hard time picking out Jennifer Hudson in a crowd. "People are like, 'You look so familiar....Did I go to school with you?'" says Hudson. "No one recognizes me anymore!"
That's because the 28-year-old star-who first won hearts as the plus-size contestant with the powerhouse pipes on American Idol
-has slimmed down to her lowest weight yet as the newest spokeswoman for Weight Watchers. "I'm loving it!" says Hudson, who gained 35 lbs. while pregnant with David Jr., her 8-month-old son with fiancé David Otunga. "After having my baby, I wanted my body back. I love a challenge, and to conquer that challenge is exciting to me."
Before Weight Watchers, Hudson dieted by limiting her meals to mostly grilled chicken and egg whites. "I was avoiding all these foods. I haven't had ice cream in 10 years!" says Hudson, who adds that the results were "only temporary. Then you go right back to where you came from." But since joining Weight Watchers in January, Hudson learned how to incorporate more fiber and vegetables into her meals. Now she even indulges in small servings of foods she once swore off, like turkey wings and pizza. "She's finding a safe middle ground," says her Weight Watchers leader Liz Josefsberg.
The Chicago-bred singer is used to seeing her weight fluctuate up and down the scale. For her film debut in 2006's Dreamgirls
, Hudson gained more than 20 lbs. to play Effie White by devouring "cakes and cookies and lots of fried food," she said. But by the time Hudson started collecting awards for her knockout performance, she had dropped 25 lbs. and returned to "Jennifer size." Just two years later Hudson found out she was pregnant with her first baby with Otunga, a WWE wrestler. "I'm pregnant, I have the right to gain as much as I want!" Hudson said.
Now as she continues to lose a steady 1 to 2 lbs. a week, Hudson takes every opportunity to "buy the whole mall" when her clothes feel baggy. As for her "classic and traditional" wedding gown for her upcoming nuptials? "I've had I don't know how many fittings because each time I'm like, 'We're going to have to refit!'" says Hudson, who didn't disclose any details about her big day. "It's crazy." But despite all the dramatic changes, one thing remains the same. "I was just as comfortable then with my body," says Hudson, "as I am now."