LOS ANGELES (AFP) - Renee Zellweger hit back on Wednesday at the online furore triggered by her new-look face, saying she was simply older and happier.

The 45-year-old Oscar-winner, whose first film in five years is out next year, told People magazine she had not been "taking care of myself" and was exhausted, but is now back to health.

"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," Zellweger said, calling the storm about her appearance "silly".

"It seems the folks who come digging around for some nefarious truth which doesn't exist won't get off my porch until I answer the door," the Bridget Jones star told People as she explained her decision to speak out.

Zellweger sparked a global firestorm of online comment after she appeared at a Hollywood women's awards show Monday.

Her face appeared radically different, fueling talk that she had had plastic surgery.

The star, who shot to fame in 2001's Bridget Jones' Diary and 2004 sequel Bridget Jones: The Edge Of Reason, won a best supporting actress Oscar for 2003's Cold Mountain and has three Golden Globes to her name.

But she has not appeared in a new film since 2010's My Own Love Song. Her latest movie, The Whole Truth, is due out next year.

Zellweger told People: "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, she said.

"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."

Meanwhile, some have come to the defence of the actress, with the Washington Post calling out the hypocritical obsession over one woman's possible plastic surgery when "Americans had more than 11 million cosmetic procedures in 2013".

Comments on the People Magazine's website were predictably negative, with many saying how unrecognisable the actress now is.

But a few stood up for her. One reader who went by the name Srift said: "Renee looks great. Before and now. Was her choice. Live with it. She's still Renee Zellweger. Plus she still has that super attractive voice and laugh. So let's all be merry and chill."