Sight is precious, most people would rather die earlier or lose a limb than their vision. Vitamins can keep your eyes healthy. Vitamin A deficiency for example is the most common form of malnutrition leading to eye disease and the leading cause of childhood blindness worldwide. The World Health Organisation (WHO) has estimated that approximately 228 million children are affected. Most children with Vitamin A deficiency live in developing countries but recently I reported cases in Australia in children on a diet of chips and coke. Supplementation with Vitamin A is only needed if there is dietary deficiency. Care must be taken with Vitamin A supplements as in excess Vitamin A can have toxic effects on vision, the bones and skin. In pregnant women excess Vitamin A can harm the baby’s eyes, skull, lung and heart.
Vitamins can prevent age-related macular degeneration (AMD), the most common cause of blindness in the elderly in the developed world, from getting worse. A large study, the Age-related Eye Disease Study (AREDS), found that the risk of developing advanced AMD was reduced with vitamin C, vitamin E, beta-carotene, zinc and copper. Beta-carotene however was associated with an increased risk of lung cancer. The next study, AREDS 2 found that lutein and zeaxanthin together appeared to be a safe and effective alternative to beta-carotene. The Royal Australian and New Zealand College of Ophthalmologist’s (RANZCO’s) ‘Choosing Wisely’ campaign advised patients to only take vitamin supplements if they are at risk of their macular degeneration causing significant loss of vision. Patients were advised to have an eye check to find out if they need to take the AREDS vitamin formula. Clinical studies have not shown a benefit from supplementation at the early stages of AMD or where there is no AMD. A healthy diet is all that is needed for patients with early AMD to obtain the necessary vitamins and minerals from a healthy diet that includes fruit, dark green leafy vegetables, fish and nuts. ‘Choosing Wisely’ meant that people would not have the inconvenience of having to take supplements in addition to their usual medications.\
The benefit of other vitamins to eye health is less certain. Currently there is no proof that multivitamins lower the risk of cataract in healthy people. Limited evidence suggests that they may be beneficial in the setting of malnutrition.
Although vitamins are essential for vision in most cases a healthy balanced diet, quitting smoking, regular exercise, and maintaining a healthy weight are more important than vitamin supplements.
About the Author – Professor Stephanie Watson BBSc(Med) (Hons I), MBBS (Hons I), PhD, FRANZCO
Professor Stephanie Watson is an international leader in research and innovation at the Save Sight Institute, University of Sydney. Her research programme focuses on innovative solutions to restore sight from and promote eye health in corneal disease whilst training the next generation of eye experts. Stephanie has provided expert advice to the Vitamania team, she was also the ophthalmologist who diagnosed Cian Moore with vitamin A deficiency and subsequently treated him.