Chemist Chad Jones explains why parents tell their children that carrots are good for their eyes. (Reactions/American Chemical Society)

When you're trying to feed an ornery kid some vegetables, you want to believe that all the rumors are true: Spinach will give you Popeye-like muscles, and carrots will give you super-human vision. Unfortunately, spinach is pretty much as good for you as any other green veggie, and scarfing raw carrots won't help you ditch your contact lenses.

A new video from the American Chemical Society gets into the fascinating history of the carrot rumor: It's actually a story of wartime espionage.

In World War II, British pilots had a game-changing new tool for finding their enemies at night -- RADAR. But if the enemy knew about the Allies's new tech, they'd undoubtedly start working on copying it. So the British military started a rumor that their pilots had high-carrot diets to thank for their new-found night vision. From myth-busting Web site Snopes:

News stories began appearing in the British press about extraordinary personnel manning the defenses, including Flight Lieutenant John Cunningham, an RAF pilot dubbed "Cats Eyes" on the basis of his exceptional night vision that allowed him to spot his prey in the dark. Cunningham's abilities were chalked up to his love of carrots. Further stories claimed RAF pilots were being fed goodly amounts of this root vegetable to foster similar abilities in them.

It's not clear how well the ruse worked on the German forces, but it certainly worked wonders on the Brits: People started eating carrots so that they'd be able to see better during blackouts. When food shortages led the government to push home-grown veggies as an alternative to rations, the carrot myth was pushed further to encourage citizens to cultivate them at home.

This isn't to say that carrots aren't good for your eyes: They're a nice source of Vitamin A, which is essential for the general health of your eyes (and hair, skin, and immune system). But while it's important to eat sources of Vitamin A (which also include lettuce, milk, cheese, and peas, among other things), eating more won't actually help you see any better.

In fact, shoveling excess carrot puree into your darling child's mouth will probably just make them look a little yellow. So even if you're hoping to raise a kid with fighter-pilot-class-peepers, rotate the veggie selection every once in a while.