A study of older women found that those who had the highest levels of the vitamin, found in oily fish and eggs as well as dietary supplement pills, were nearly 60 per cent less likely to contract age-related macular degeneration.
Scientists believe it has anti-inflammatory properties that can help prevent the incurable condition by stopping the eyes being damaged.
Their research indicates that taking in more Vitamin D through food or tablets, rather than sunlight, can help protect against developing AMD.
However the researchers recommend that older people talk to their doctors first to see if they need to take supplements. Some studies have warned against taking large amounts of the vitamin, which also helps reduce cancer risk, because in high doses it is thought to weaken bones.
"In conclusion, Vitamin D status may significantly affect a woman’s odds of developing early AMD," the study said.
AMD, which is thought to have left 230,000 people in Britain partially blind, is the leading cause of blindness worldwide.
There is no cure for the condition, caused by progressive damage to the centre of the retina at the back of the eye, and treatment to reduce the symptoms is limited and costly.
"Therefore it is important to identify modifiable risk factors that may affect disease occurrence or prevent progression to advanced stages," says the paper published in the journal Archives of Ophthalmology.
It suggests that one way older people can help protect their eyesight is by ensuring they take enough Vitamin D.
Researchers studied 1,313 post-menopausal American women aged between 50 and 79.
They tested the levels of a substance called serum 25(OH)D in their blood, which reflects Vitamin D intake, and also asked them about their diet and how much time they spent outdoors.
Several years later examined the women to see how many were losing their sight.