The Oscar-winner responded to critics by saying, "People don't know me in my forties. Perhaps I look different. Who doesn't as they get older?"
She might be the latest target of media scrutiny, but Zellweger is certainly not the first celebrity to drastically alter her appearance. Here’s a look at other celebrities who have changed their looks over the years:
John Travolta came on the scene as the hunky young heartthrob in movies like Grease and Saturday Night Fever, but noticeable changes to his hairline and face have raised eyebrows at recent public appearances.
Actress and reality star Tori Spelling put the rumor mill to rest in 2008, admitting to Entertainment Weekly that she had a nose job and breast augmentation surgery in her twenties.
"I’ve had the two procedures that probably every other woman in Hollywood has had done," Spelling confessed.
Rapper Lil’ Kim made headlines with her scandalous purple jumpsuit and pasty combo at the 1999 MTV Video Music Awards, but it was her appearance at the awards show 14 years later that really got people talking. The Junior M.A.F.I.A. member was nearly unrecognizable in 2013.
Actress and singer Ashlee Simpson never publicly admitted to plastic surgery, but nose job rumors were rampant after the starlet stepped out of big sister Jessica’s shadow with her own hit records and reality show – and a far slimmer facial profile.
Dad/manager Joe Simpson admitted in a Fox News interview that, "There was a real problem with her breathing and that was cured."
Click the gallery below to check out some more surprising star transformations.