Scientists in the UK claim that dieting for two days a week could reduce the risk of developing breast cancer by nearly 80 per cent.
Researchers from Manchester's Withington Hospital are looking for women to take part in a supervised diet that would restrict them to 600 calories a day.
The diet will consist of mainly fruit and vegetables and would be roughly a third of the daily recommended calorie intake.
The experiment follows research on mice by Wisconsin University, which found that a strict diet for two days of the week combined with a normal diet for the other five days cut the risk of cancer from 77 per cent to three per cent.
"It's an amazing figure, which is why we want to test it in people," said Dr Michelle Harvie, of Withington's Genesis Centre, who is set to lead the research.
The researchers are warning that women are not being encouraged to "crash diet".
"This is a supervised calorie-controlled diet. Our volunteers will be screened so we know they are medically able to undergo it," Dr Harvie stressed.
The scientists are looking for volunteers between 40 and 45 years old for the six-month study who have a history of breast cancer in their family.