Many described the 45-year-old actress as "unrecognizable" with some attributing the star's appearance to cosmetic surgery. A number of plastic surgeons weighed in on the possible work she may have had done.

"The big thing that strikes me is her eye shape has changed from almond to oval," speculated plastic surgeon, Dr. John Scheibelhoffer who has not treated Zellweger, to Fox News. "Her eyes are much more open. The bottom third of her face doesn't look all the different. She could have done fillers in her cheeks, her nose doesn't look all that different."

Zellweger was quick to respond to the buzz surrounding her looks: "I'm glad folks think I look different! I'm living a different, happy, more fulfilling life, and I'm thrilled that perhaps it shows," said the "Jerry Maguire" star to People.

She viewed the rumblings about her looks as "silly" and any alternations to her appearance is because she's going through a "growing period" as she enjoys where she's at in life.

"My friends say that I look peaceful. I am healthy," continued the "Cinderella Man" star. "For a long time I wasn't doing such a good job with that. I took on a schedule that is not realistically sustainable and didn't allow for taking care of myself. Rather than stopping to recalibrate, I kept running until I was depleted and made bad choices about how to conceal the exhaustion. I was aware of the chaos and finally chose different things."

One thing is for sure, the Oscar-winning actress looked spectacular in her black dress. Zellweger was dressed to impress with a black knee-length ensemble with a sheer-embroidered neckline and sleeves. She accented the look with simple but elegant pieces including a gold clutch and and matching pumps.

She set her hair in a wavy romantic side-part and looked absolutely radiant with natural makeup and a touch of pink lip shimmer.

"People don't know me [as] healthy for a while," said the blonde beauty. "Perhaps I look different. Who doesn't as they get older?! Ha. But I am different. I'm happy," concluded Renee to People.

What do you think? Is she aging gracefully or with the help of cosmetic professionals?