Which vitamin is commonly associated with vision?

• A. Vitamin C
• B. Vitamin A
• C. Vitamin D
• D. Vitamin B12

Answer: (B)

Vitamin A is the nutrient most closely linked to vision because its active form, retinal, is essential for the photochemical reactions that detect light. Retinal combines with the protein opsin to form rhodopsin in rod cells, which enables you to see in dim light. When light hits rhodopsin, it changes and triggers a signal sent to the brain; retinal is then recycled back to its original form so vision can continue, especially in low-light conditions. Beyond the visual cycle, vitamin A helps maintain the health of the corneal and conjunctival surfaces, so deficiency can cause dryness and keratinization that further affect vision. Dietary vitamin A comes as preformed vitamin A in animal products and as provitamin A carotenoids (like beta-carotene) in plants, which the body converts to retinal. While other vitamins support overall eye health, none are as directly tied to the core process of vision as vitamin A.