Nutritional and potential disease prevention properties of carotenoids

Epidemiological studies have shown that people who consume diets with a high content of vegetables have a reduced risk of degenerative diseases such as specific cancers, cardiovascular disease, age-related macular degenerative disease (AMD), and cataracts. There is no convincing evidence that the protective role of vegetables against cancer and cardiovascular disease is due to carotenoids. However, there is a strong possibility that lutein and zeaxanthin present in food materials may prevent AMD and cataract formation. Increased use of cooked tomato products also has been shown to reduce prostate cancer risk as a result of increased bioavailability of cis-lycopene. One of the most important biochemical mechanisms underlying the cancer-preventive activity of carotenoids is the stimulation of intercellular gap junction communications. P-Carotene, canthaxanthin, and lutein are efficient inducers of intercellular gap junction communication, whereas a-carotene and lycopene are less active.