The belief that eating carrots (Daucus carota spp. sativus) improves night vision is well-known, and is sometimes said to have originated  from government propaganda during World War II.

According to a brief report in The Times of 10 October 2015, a study led by Harvard University, studying 100,000 over-50s for 25 years, suggests that carotenoids – ‘which give carrots, peppers [Capsicum cvs] and spinach [Spinacia oleracea] their colours can slow the onset of age-related macular degeneration’.  People who ate the most carotenoides ‘had a 40% lower risk of the condition.’