Beta-carotene is the one you all know. The human body can convert some carotenoids to vitamin A. In fact, there are 60 carotenoids that we can convert to vitamin A, beta-carotene is just the most common.
For most populations, carotenoids are the major source of vitamin A in the diet. Animal foods provide a rich source of retinol, which also has vitamin A activity in the body. The Native American Eskimo population derives most of its vitamin A from animal foods as their sources of plant food are somewhat limited.
Most of the carotenoids can not be converted into vitamin A. In fact there are over 600 known carotenoids, so less than 10% are used to make vitamin A.
Carotenoids give plants the colors yellow, red, and orange. They create the fall foliage as the chlorophyll production slows this time of year. Carotenoids facilitate photosynthesis and act as anti-oxidants. The non-provitamin A carotenoids also function as anti-oxidants in the human body. It has been suggested that the carotenoids may account for the protective benefits of diets high in fruits and vegetables against cancer and other chronic diseases.
