Charlize Theron, pictured at the Fast X premiere in May, says she's never gone under the knife. Photo / Getty Images

Hollywood star Charlize Theron has responded to cruel rumours claiming she’s had “bad plastic surgery”, revealing she’s never gone under the knife to alter her appearance.

In an interview with Allure magazine, the 48-year-old said: “My face is changing. And I love that my face is changing and ageing. People think I had a facelift. They’re like, ‘What did she do to her face?’ I’m like, ‘B***h, I’m just ageing! It doesn’t mean I got bad plastic surgery. This is just what happens.’”

The Monster actress, who has been the face of Dior’s J’Adore fragrance for two decades, added that even though she’s never undergone cosmetic surgery, she doesn’t frown upon those who have.

She also addressed the unequal attitudes toward gender and ageing.

“I’ve always had issues with the fact that men kind of age like fine wines and women like cut flowers.

“I despise that concept, and I want to fight against it. But I also think women want to age in a way that feels right to them.

“We need to be a little bit more empathetic to how we all go through our journey,” she said.

And while Theron has no qualms about her changing appearance, she says she does lament the body she had when she was younger.

“More than my face, I wish I had my 25-year-old body that I can just throw against the wall and [it will] not even hurt tomorrow. Now, if I don’t work out for three days and I then go back to the gym, I can’t walk.”

She said her ageing body and past experiences will have more of an impact on the acting roles she chooses in the future.

“I will never, ever do a movie again and say, ‘Yeah, I’ll gain 40 pounds (18kg).’

“When I was 27, I did Monster. I lost 30 pounds (13kg) overnight. I missed three meals, and I was back to my normal weight. Then I did it at 43 for Tully, and I remember a year into trying to lose the weight, I called my doctor and I said, ‘I think I’m dying because I cannot lose this weight.’”

But her doctor assured her that wasn’t the case.

“He was like, ‘You’re over 40. Calm down.’ Nobody wants to hear that.”