When I was a kid, my parents often tried to sell me on the idea that carrots were good for my eyes—and if I wanted to avoid vision correction in the future, I would eat them now. But after I was fitted for my first pair of glasses in fourth grade, they dropped that line and served carrots with a side of ranch dressing and buffalo wings. As I’ve mentioned before, my mom was not exactly scientifically rigorous in her parenting, so I can’t help but wonder if there’s any truth to what she was telling me about carrots and vision.
It seems that Mom was just parroting a commonly held belief that got its start as a bit of wartime propaganda.
During World War II, German planes frequently made bombing runs over Great Britain. In the early 1940s, the British set up a chain of radar stations along the southern coast of England so German bombers could be detected and shot down before they reached land. Not wanting the Germans to know that they had this technology, the British intelligence service began a propaganda campaign focused on the incredible eyesight of the soldiers manning the defenses—including Flight Lieutenant John Cunningham, an RAF fighter pilot dubbed "Cat's Eyes" for his ability to spot bombers in the dead of night.
Cat's Eyes' amazing vision was chalked up to his carrot-heavy diet. The campaign spilled over to the Ministry of Food, which produced informative cooking pamphlets on carrots and other root vegetables, often featuring a character called Dr. Carrot and the slogan “Carrots keep you healthy and help you see in the blackout.” The Germans, British civilians, and parents all over the world bought the story and repeated it endlessly for decades to come, which helped conceal the real reason behind the RAF’s success—and got kids to eat their veggies.
The British propaganda lent carrots a little more credit than they deserve. They won’t turn you into the second coming of Cat's Eyes, but carrots are good for overall eye health because they're rich in beta-carotene, a carotenoid pigment that’s an important precursor for vitamin A. Extreme vitamin A deficiency can lead to night blindness and other eye problems—a big issue in the developing world. For most people in developed countries, though, vitamin A intake is sufficient with a well-rounded diet. For people with no vitamin A-related problems, binging on carrots won’t really improve your vision, though I think my mom will probably gloss over this fact when trying to feed my nephew.