Anorexia study blames hormones for eating disorder, not size-zero models

Scientists believe people who develop the eating disorder could have been exposed to too much of the female hormone oestrogen before their birth.

Oestrogen is naturally produced by the mother and pumped into the womb to help baby girls develop.

The link was discovered in a study of twins, which found boys with a twin sister – who would have been exposed to high levels of oestrogen in the womb – were ten times more likely to get anorexia than boys with a twin brother.

Psychiatrists believe that some mothers over-produce the hormone, which can have a long-term impact on a child's brain.

The team at the University of Sussex claims it helps explain why so many more women than men suffer from the eating disorder.

They also say their findings support arguments that anorexia is inherited rather than triggered by seeing skinny models.

Dr Marco Procopio, who looked at results for twins over 25 years, said: "Women are ten times more likely to develop anorexia than men and this goes a long way to explaining why.

"It leads us to believe that oestrogen is having a major effect in the womb.

"Too much of the hormone can make a baby into a teenage anorexic."

The study published in the American Medical Association Archives of Psychiatry gives credence to research which suggests the brains of anorexics behave differently to those of non-anorexics.

He added: "One thing we are certain of is that there is a genetic disposition to the eating disorder."

Susan Ringwood, of the eating disorders charity Beat, said: "This is interesting, although it is important that we also look at other factors such as body image."

Dr Dee Dawson, of the North London Rhodes Farm clinic for anorexics, said the condition was often sparked by problems at home. But he accepted physical reasons might make some teenagers more susceptible.