Library.

“Eating carrots significantly improves night vision in humans.”

This claim is misleading. Carrots contain beta-carotene, which the body converts to vitamin A — essential for rod cell function in the eye. However, eating carrots only restores night vision in people who are vitamin A deficient; it does not enhance night vision beyond normal levels in well-nourished individuals. The strongest clinical trial cited used carotenoid supplements, not carrots. The popular belief largely traces back to WWII British propaganda designed to conceal radar technology. For most people in developed countries, extra carrots will not meaningfully improve night vision.

“Vitamin A can cure measles.”

Vitamin A does not cure measles. The WHO, CDC, and American Academy of Pediatrics all classify vitamin A as supportive or adjunct care that may reduce complications and severity — particularly in vitamin A-deficient children — but explicitly state it does not eliminate the measles infection. Reducing morbidity or complications is categorically different from curing a viral disease. Vaccination remains the only proven method of prevention, and no treatment eradicates measles once contracted.