SYDNEY, Oct. 19 (Xinhua) -- Eating green leafy vegetables could help prevent the macular degeneration eye disease, a major cause of blindness, according to latest Australian research.

The study, which looked at more than 2,000 Australian adults over a 15-year period, showed that vegetable nitrates found mainly in green leafy vegetables as well as beetroot could help reduce the risk of developing the disease, the Westmead Institute for Medical Research said in a statement about its findings on Friday.

"This is the first time the effects of dietary nitrates on macular degeneration risk has been measured," said lead researcher Associate Prof. Bamini Gopinath.

"Essentially we found that people who ate 100 to 142 mg of vegetable nitrates every day had a reduced risk of developing early signs of macular degeneration compared with people who ate fewer nitrates."

Spinach has about 20 mg of nitrate per 100 gram, while beetroot has nearly 15 mg of nitrate per 100 gram, according to the institute.

The study did not show any additional benefits for people who ate more than 142 mg of dietary nitrate each day. It also did not show any significant links between vegetable nitrates and late stage age-related macular degeneration. The findings were published in the Journal of the Academy of Nutrition and Dietetics.

Macular degeneration refers to the group of degenerative diseases of the retina that cause progressive loss of central vision. One in seven Australians aged over 50 show some signs of the disease and there is currently no cure for it, according to the institute.

Age is the strongest known risk factor and the disease is more likely to occur after the age of 50, it said.