Anticancer activity of carotenoids: From human studies to cellular processes and gene regulation

Fruits and vegetables have an important role in the prevention of cancer. Carotenoids have been implicated as an important group of phytochemicals that are involved in cancer prevention. However, when reviewing data related to the chemopreventive effects of phytochemicals, one should bear in mind that the use of a single carotenoid or any other micronutrient as a “magic bullet,“which had been successful in in vitro and in vivo models, did not prove as favorable in human intervention studies. In contrast, accumulating evidence suggests that a concerted, synergistic action of various micronutrients is more likely to be the basis of the cancer-preventive activity of a diet rich in vegetables and fruit.