Renee, who is famed for playing hapless and curvy Bridget in the hit movies, caught photographers' eyes when she posed for snaps at the Elle Women in Hollywood Awards on Monday.
However, the Hollywood actress has now insisted that her remarkable change of appearance is not the result of drastic plastic surgery.
Speaking out about her new image, 45-year-old Renee insists that her look is the result of living a healthy and "peaceful" life. The star says that she "didn't take care of herself" in the past and was "exhausted".
In a statement released to People, Renee said: "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.
"My friends say that I look peaceful. I am healthy. 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."
Renne added: "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.
"People don't know me in my 40s. People don't know me as [healthy] for a while. Perhaps I look different. Who doesn't as they get older? But I am different. I'm happy."
Renee first found fame after starring in the 1996 movie Jerry Maguire, but she became a household name after landing the part of Bridget in Bridget Jones's Diary in 2001.
Following the success of the movie, Renee reprised the much-loved role for the movie's sequel, Bridget Jones: The Edge Of Reason in 2004.
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