Tracy B. is taking the antioxidant lutein in the form of mouth spray to boost and protect her vision, after reading about its remarkable properties in a new book. Lutein, found in leafy green vegetables, is vital for healthy eyes, say doctors.

Since starting on lutein spray six weeks ago, Tracy, 36, from Bradford, West Yorkshire, has noticed that her vision has got sharper, and she no longer has to wear her glasses.

'I wore glasses for ten years for close work on the computer or when I was reading or watching TV,' says the medical receptionist. 'I can see things more clearly and, overall, the quality of my vision appears better than it  has for years. I was surprised how much better I could see as a result of taking the spray.'

The condition affects around 1.8 million people in Britain and is the biggest single cause of blindness. Not everyone loses their sight completely, but most sufferers have severely restricted vision.

Eye specialists have spent years looking for ways to prevent the illness and restore people's sight. But so far there have been very few successful treatments for the illness, and none that has been permanent.

Early test results from trials with lutein offer great hope. Doctors have established that it can slow down, and in some cases reverse, the damage and loss of sight caused by macular degeneration.

Now a major trial into lutein has been started, sponsored by the U.S. Government's National Institutes of Health. Dr Ed Kondrot, a leading opthalmic surgeon in America, is convinced that lutein plays an important role in eye health and can protect against AMD.

'We know that lutein is present in high quantities in the healthy eye,' he says. 'Tests have shown that levels vary, but those with eye disease such as AMD appear to have lowered levels.

'Research is ongoing, but there is very strong evidence that lutein plays a very important part in protecting the eye from damage as well as improving the quality of vision.

'I have seen many patients with AMD whose loss of vision has been slowed down by taking lutein. But we are now fairly convinced it can protect against, as well as prevent, further damage caused by AMD.'

Dr Kondrot, who is based in Philadelphia, adds: 'The big question is, can lutein actually reverse the damage in people who have lost most or all of their sight.

'Early indications are that this can happen, and we have a number of examples of patients who were forced to give up driving because of their AMD, but who can now drive again. There are also cases of teachers, for example, who had lost most of their sight to AMD, being able to go back to work.'

In the more severe cases of AMD, Dr Kondrot uses a treatment called Microcurrent Stimulation, in addition to lutein, to clear the damage to the eye.

Like vitamin A, lutein is part of a family of antioxidants which stop the action of free radicals, which damage and destroy healthy cells.

'We knew lutein was important for eye health but didn't realise, until recently, how important it was to protect against AMD,' says Dr Kondrot.

Although a diet of leafy-green vegetables will protect the eye, even greater protection may be gained from taking it in the concentrated form of a supplement.