LONDON (Reuters) - Soul singer Amy Winehouse has developed the lung condition emphysema and has been warned by doctors that she will die if she continues smoking drugs, her father said in an interview on Sunday.Mitch Winehouse said the incurable illness, which leaves sufferers struggling for breath, was diagnosed when his daughter had series of health checks in hospital.

"The doctors have told her if she goes back to smoking drugs it won't just ruin her voice, it will kill her," he was quoted as saying in the Sunday Mirror. "The doctors have said that if she had continued the way she was going she could have ended up an invalid -- she wouldn't have been able to breathe."

He added: "She's got emphysema. It's in its early stages, but had it gone on for another month they painted a very vivid picture of her sitting there like an old person with a mask on her face struggling to breathe.

"With smoking the crack cocaine and the cigarettes, her lungs are all gunked up. There are nodules around the chest and dark marks. She's got 70 percent lung capacity."

He added that a spell in hospital last week and renewed treatment for her well-publicized drug addiction had offered a ray of hope for his 24-year-old daughter.

"If she doesn't go back to drugs, then she can lead this magnificent life," he said. "We are praying that that's what Amy really wants. She seems resolute."

He called on drug dealers to help her recovery by refusing to supply her with crack cocaine.

There is no medical reason why she shouldn't be able to perform at the Glastonbury Festival next weekend, he added. In the past, work has helped to keep her away from drugs.

"If she hadn't done recent shows in Moscow and Portugal she could have been dead by now," he said. "She abstains and regulates her drug use when she has to do a show."

Winehouse won five Grammy Awards in February and enjoyed commercial success with her album "Back to Black."

Source: Reuters