Carotenoids are fat-soluble plant pigments that give fruits and vegetables their bright red, orange, and yellow colors. Many carotenoids can be converted by the body into vitamin A, an essential nutrient for vision, immune function, and cellular health. The most familiar carotenoid is beta-carotene, which also has the greatest vitamin A activity among the carotenoids. Other carotenoids include alpha-carotene, lycopene, lutein, astaxanthin, beta-cryptoxanthin, and zeaxanthin.
For many years, the primary value attributed to carotenoids was their role as vitamin A precursors. More recent research has shown that carotenoids have additional biological activity. They function as antioxidants, helping protect cells from oxidative damage. Research also suggests that carotenoids support immune function and may play a role in protecting against cancer. Some carotenoids appear to enhance communication between cells, a process that may help regulate normal cell growth.
Beta-carotene, alpha-carotene, and beta-cryptoxanthin are commonly found in orange-colored fruits and vegetables such as carrots, squash, sweet potatoes, yams, apricots, and mangoes. Dark green vegetables are also rich sources of carotenoids, particularly beta-carotene and lutein, although the green color of chlorophyll masks their presence. Tomatoes are a major source of lycopene, which is also found in foods such as pink grapefruit and guava.
Because of the wide range of biological functions attributed to carotenoids, diets rich in brightly colored fruits and vegetables are consistently associated with better health outcomes. Regular consumption of these foods supports antioxidant defenses, immune health, and long-term cellular protection.
