The eyes are not just a window to the soul; they may be a surprisingly reliable guide to how healthily you eat. While there is no correlation between refusing to eat your carrots and actual night vision, nutrition and optical health are closely linked, with scientists currently looking at the role played by vitamins and minerals in the prevention of eye diseases, such as age-related macular degeneration (AMD) and cataracts.
That a link exists has long been understood: the eye condition xerophthalmia, a common cause of blindness in developing countries, is known to be caused by a lack of vitamin A, which is found in sources such as meat and fresh vegetables.
In fact, vitamins and minerals are crucial to eye health, as they are constantly required to help ward off damage caused by UV light rays. A healthy blood supply is necessary to supply nutrients and oxygen to the eye. So, conditions such as high cholesterol, which clog arteries elsewhere in the body, are also important in the eye region.
Professor Ian Grierson, head of ophthalmology at the University of Liverpool, is one of the pioneers in nutritional research. He says: “It is quite difficult to show real benefit to an individual, that by changing their diet it will benefit their sight – the studies needed would be too big and expensive.”