Are Carrots Really Good For Your Eyes?
You may have been told to eat more carrots to help with night vision, but where did this advice come from? It dates back to World War II when the British Air Force successfully gunned down German aircraft in the middle of the night. It was pitch black; how did they do it without any technology to help them see? The UK Ministry of Food (which no longer exists) claimed it was because the pilots ate a lot of carrots (via Scientific American). There was even a propaganda campaign about how the pilots' carrot diet improved their night vision so well that they could take down enemy planes in the dark. These advertisements encouraged civilians to do the same thing to help them function better during blackouts.
But it wasn't a diet rich in carrots that helped the British Air Force defeat German aircraft; it was new radar technology used to spot and shoot down enemy planes. They wanted to hide the fact that they had this technology, so someone came up with the carrot diet — but they weren't wrong about carrots' health benefits (via Berkeley Wellness).
How carrots help eye health
Whoever came up with the carrot diet rumor during World War II might have known that carrots are actually good for your eyes. Carrots contain beta carotene, which our bodies turn into retinal, a form of vitamin A, which is essential for eye health. Most people get enough vitamin A through a healthy diet. Some people are vitamin A deficient due to a poor diet, alcoholism, or problems with absorbing the vitamin. In some cases, a lack of vitamin A due to a poor diet or malnutrition can cause blindness. Vitamin A does help people see in low light conditions. If you don't get enough vitamin A, your cornea (the clear part in the front of your eyes) can disappear.
The vitamin A from carrots isn't going to allow you to see in the dark, but it can help with age-related macular degeneration (AMD), according to the Age Related Eye Disease Study (AREDS). The study found that a supplement containing beta carotene, vitamin C, copper, vitamin E, and zinc helped keep people with intermediate AMD from progressing into advanced AMD, which leads to blindness.
How much vitamin A do you need? Adult women need 700 micrograms, and adult men need 900 micrograms of vitamin A daily (via National Institutes of Health Office of Dietary Supplements).