Is it true that carrots help your night vision?

Depends: The basis for this "old wive's tale" is that, accurately, carrots as well as other yellow/orange vegetables and gourds (squash, pumpkin) are fantastic sources of vitamin a, an essential vitamin required for photoreceptor (cone/rod) metabolism. While severe vitamin a deficiency may lead to serious, but generally reversible, vision problems, such as night blindness, most people in developed countries meet more than their daily vitamin a requirements from normal diets and there is no need to consume exorbitant amounts of carrots. In fact, vitamin a excess may be toxic to the liver and some clinical studies have demonstrated that excess vitamin a metabolites may actually be potentially toxic to photoreceptors.

To a degree: Carrots contain a high level of vitamin a, which is important for the proper functioning of the receptors in the retina (the eye's film layer). People who are deficient in vitamin a can develop night blindness, but it rarely occurs in developed countries. In fact, we usually ingest enough vitamin a from meats and vegetbles in our regular diet that it often does not need to be supplemented.