bjones
|
The belief that carrots improve vision is a common misconception held by many people and supported by many doctors. Carrots do not improve vision. The main factor why so many people believe that it does is due to the semantics of language. Carrots contain high amounts of vitamin A in the form of beta carotene. Once eaten, the liver changes beta carotene into vitamin A. The vitamin A is then absorbed by the cells of the retina in the eye. Someone who doesn’t have enough vitamin A runs the risk of impairing their vision to the level of complete blindness. One carrot provides 400% the recommended daily allowance of vitamin A, so one carrot per day is more than enough to keep the eyes healthy.
The problem with the statement that carrots improve vision is due to the word “improve.” Although carrots help to maintain eye health and normal eyesight, they do not improve vision. No substance known to modern man can improve vision. Eating carrots will not increase your visual capabilities. Carrots will neither make you see better in the dark, like a cat, nor will they make you see farther and sharper, like a hawk. Visual capabilities are limited by genetic and physiological factors that humans have yet learned to manipulate for a positive effect. While carrots may bring the vision of malnourished people back to normal, they will do nothing for people who are already healthy.
The misconception of improved vision from carrots is mostly due to misreading the statement, but some studies have also been misconstrued. One study showed that vitamin A is used by the retina and converted to rhodopsin. Rhodopsin is a purple pigment in the eye that is used for night vision, but no evidence exists showing that increased rhodopsin improves night vision. Also, among the first signs of vitamin A deficiency is a decrease in night vision, so consuming carrots can bring vision back to healthy levels but not beyond what genetics and the physical condition of the eye allows.
 Posted 5394 day ago
|