Experiments in animals also revealed that a diet containing saffron can protect the eye from damage caused by bright sunlight and slow the progress of genetic diseases such as retinitis pigmentosa.
The researchers also found saffron had a beneficial effect in humans suffering from age-related macular degeneration, the most common form of blindness in old age.
Macular degeneration affects more than 500,000 people in the UK and around two per cent of people aged over 50 years old suffer from the disease, which is caused by the gradual damage to cells on the retina at the back of the eye.
Early tests by the researchers, however, have revealed that patients showed signs of cell recovery after being given saffron in their diet.
The scientists, who are based at the University of L'Aquila, in Italy, and Sydney University, in Australia, are now conducting a clinical trial on human patients with age-related macular degeneration.
Saffron has been used in cooking for thousands of years and is a key ingredient in dishes such as paella, risotto and pilau rice.
The spice is produced from the dried stigmas – the part of the plant where pollen grains germinate – of the lilac coloured flower, Crocus sativus.
Each flower contains three threadlike deep red stigmas that give food a rich yellow colour and subtle flavour.
High quality saffron can cost up to £500 for just one pound of the spice, but historically it has cost more than its weight in gold and was the source of lucrative spice trading.
Professor Silvia Bisti, who led the research from the University of L'Aquila, said: "Saffron seems to possess a number of properties that are protective to vision.
"We are now trying to understand the mechanism, but it appears to block cell death. Saffron components have strong antioxidant properties.
"It also appears to affect genes which regulate the fatty acid content of the cell membrane and this makes the vision cells tougher and more resilient."
The researchers found that feeding rats around one strand of saffron a day helped to protect the animals against damage to their eyes from bright light while also slowing the progression of retinitis pigmentosa, an inherited disease that causes progressive sight loss and affects one in every 4,000 people.
Barbara McLaughlin, campaigns manager for the Royal National Institute of Blind People, said: "The first results of small scale trials of saffron in humans seem very encouraging.
"Clearly, a lot more research is needed to understand how saffron affects the eye and whether it could be turned into an effective treatment."
Written by: Richard Gray, Science Correspondent
Read the entire story:http://www.telegraph.co.uk/science/science-news/5522063/Saffron-can-protect-against-eyesight-loss.html#.TmpUtzcgj84.email
