Sarah Jessica Parker's obsession with exercise is beginning to wreak havoc on her body, causing bulging veins in her hands and wiry arms.
Shocking new un-retouched snaps of the 'Sex and the City' star show her looking skeletal while out and about in New York.
And the 45-year-old actress' pals are now worried about her health - saying that stress, an obsession with working and a fear of ageing have made her frighteningly gaunt.
"Her weight loss is extreme, but it's down to complete and utter stress. She has lost another stone and she's a size zero too," News of the World quoted a pal as saying.
The actress, who has twin ten-month-old daughters from a surrogate mum and a seven-year-old son with actor husband Matthew Broderick, has been occupied working on 'Sex and the City 2', which opens in Britain on May 28.
And she is said to spend an hour every day doing pilates, desperate to keep in shape.
"Pilates is the main part of her regime. She doesn't do lots of cardio in the gym. But she doesn't eat a lot either and has been known to do some crazy diets at times. It's not healthy," the pal said.
According to another pal, Sarah is also paranoid about getting old.
The friend said: "Her weight is all tied in with how old she is. She has a real fear of ageing. She thinks if she stays thin it will stop that."