Former model Kate Fischer says her doctor has given her a dire health warning.

Former model and actress Tziporah Malkah (previously known as Kate Fischer) says she has been issued a dire warning by doctors following her recent weight gain.

Speaking to New Idea this week, the 42-year-old said that the health implications associated with her weight could shave up to 20 years off her life if action isn’t taken. And it’s a warning, she says, that has hit home.

"I'm way too heavy, and it's time to trim down," Malkah said.

Emphasising that her decision is based on health and not size, James Packer's former fiancee continued, "This is doctor's orders - he says I'm morbidly obese. My blood pressure is high and I'm likely to die prematurely unless I lose weight. So my life depends on this."

Like many women, Malkah has struggled with her weight throughout the years. At the peak of her modelling career in the 90s she was lauded as one of Australia's great beauties.

Speaking about the public's obsession with her former self in October when she graced the cover of New Idea, Malkah simply said, “At the moment I’m fat. Get over it!”

“It’s important women of all ages and shapes know they still have a place and a voice. So if I can now inspire other women by doing a shoot like that myself, then great!” she said.

“I am in no way condoning being overly fat – it’s not healthy, nor is being underweight for that matter. But I am saying we all should be more accepting of people’s beauty in all shapes and sizes.”