Anorexia can cause serious eye damage

The eating disorder anorexia nervosa can cause potentially serious eye damage, scientists have discovered.

In a small study, scientists at the University of Athens compared the thickness and electrical activity of the macula in both eyes of 13 women with anorexia nervosa and in 20 healthy women of the same age.

The macula is the light sensitive tissue in the centre of the retina at the back of the eye, and is responsible for fine detailed central vision and the processing of light.

The women with anorexia had suffered from the condition for an average of 10 years.

In women with anorexia, the scientists found the macula and nerve layers feeding it were significantly thinner than those of healthy women.

There was also significantly less firing of the electrical neurotransmitter dopamine in the eyes of the women with anorexia nervosa. Dopamine neurotransmission plays an important role in how the brain processes visual images.

The scientists also said there appeared to be differences between women with different patterns of anorexia.

The fovea - a small area at the centre of the macula that is rich in light sensitive cells - was thinner in those women who binged and purged than in those who simply severely restricted the amount of calories they consumed.

In developed countries, anorexia nervosa affects up to three per cent of affluent women. Although the condition also increasingly affects men, around 10 women will be affected for every one man.

Writing in the British Journal of Opthalmology, the scientists said it was not yet clear whether macular thinning and reduced electrical activity were the start of progressive blindness or whether the eyes would return to normal once the women resumed a normal diet.

This article was published on Fri 29 October 2010