Research has shown that age-related macular degeneration (AMD), an eye disease that causes partial blindness caused by progressive damage to the centre of the retina at the back of the eye, may be prevented by women taking vitamin D supplements.
AMD, which is thought to have left 230,000 people in Britain partially blind, is the leading cause of blindness worldwide.
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.
They found that among those aged under 75 who had the highest intakes of Vitamin D were far less likely to develop early AMD, although this did not hold for older women.
Those who took an average of 720 International Units (18 micrograms) a day were 59 per cent less likely to develop the condition than those who took less than 120 IU (3 micrograms).
The scientists suggest that Vitamin D, which has anti-inflammatory properties, may stop the "destructive inflammation" in parts of the retina that lead to AMD.
Only vitamin D consumed through food and supplements - not absorbed via the sun - were found to have the association.
In the study, it was discovered the top food sources among the participants were milk, fish, fortified margarine and fortified cereal.
The scientists, led by Dr Amy Millen, from Buffalo University, New York, wrote in the journal Archives of Ophthalmology: 'More studies are needed to verify this association as well as to better understand the potential interaction between vitamin D status and genetic and lifestyle factors with respect to risk of early AMD.'