As kids, it was commonplace for adults to preach about the importance of vegetables and how carrots could help you see better at night. But does eating carrots really improve your night vision?
The idea first originated in the early 20th century during World War II, at a time when the British were subjected to nightly German bombings. Eventually, the British devised radar stations that were used to detect these German aircrafts passing overhead. However, in order to ensure that German intelligence would not catch on, the British spread propaganda that improved night vision from eating carrots was how they detected German bombers at night.
And there is a grain of truth in the matter. Carrots contain vitamin A, which is a key building block of molecules responsible for both low-light and color vision. It is the light-sensitive part of rhodopsin, a protein in rod cells in the retina of the eye that is particularly sensitive to light. People who are deficient in Vitamin A may not see as well at night. But Vitamin A and carrots do not improve sight in individuals that have sufficient vitamin A. The fact that health advice can be based on old war propaganda is one of the reasons we encourage you to always “Think Twice.”
https://www.centreofthecell.org/blog/science-questions/will-eating-carrots-give-me-night-vision/
https://www.sciencefocus.com/the-human-body/do-carrots-really-help-you-see-in-the-dark/