Researchers at the Westmead Institute for Medical Research interviewed more than 2,000 Australian adults aged over 50 and followed them over a 15-year period.

The research showed that people who ate at least one serving of oranges every day had more than a 60% reduced risk of developing late macular degeneration 15 years later.

Lead Researcher Associate Professor Bamini Gopinath from the University of Sydney said the data showed that flavonoids in oranges appear to help prevent against the eye disease.

“Essentially we found that people who eat at least one serve of orange every day have a reduced risk of developing macular degeneration compared with people who never eat oranges,” she said.

“Even eating an orange once a week seems to offer significant benefits.

“The data shows that flavonoids found in oranges appear to help protect against the disease.”

Associate Professor Gopinath said that until now most research has focused on the effects of common nutrients such as vitamins C, E and A on the eyes.

“Our research is different because we focused on the relationship between flavonoids and macular degeneration.

“Flavonoids are powerful antioxidants found in almost all fruits and vegetables, and they have important anti-inflammatory benefits for the immune system.

“We examined common foods that contain flavonoids such as tea, apples, red wine and oranges.

“Significantly, the data did not show a relationship between other food sources protecting the eyes against the disease,” she said.

One in seven Australians over 50 have some signs of macular degeneration. Age is the strongest known risk factor and the disease is more likely to occur after the age of 50.

There is currently no cure for the disease.

The research compiled data from the Blue Mountains Eye Study, a benchmark population-based study that started in 1992.

It is one of the world’s largest epidemiology studies, measuring diet and lifestyle factors against health outcomes and a range of chronic diseases.

“Our research aims to understand why eye diseases occur, as well as the genetic and environmental conditions that may threaten vision,” Associate Professor Gopinath concluded.