Food Phytochemicals for Cancer Prevention I

Abstract

Laboratory animal studies and epidemiological data indicate that dietary factors play an important role in animal and human health and in the development of certain diseases, including cancer. Certain phytochemicals are able to inhibit the development of some cancers in laboratory animals. Epidemiological studies indicate that the frequent and high intake of fresh vegetables and fruits is associated with lower cancer incidence and that high plasma levels of ascorbic acid, α-tocopherol, β-carotene, vitamin A, and certain phytochemicals are inversely related to cancer incidence. This evidence suggests that some constituents of fruits and vegetables may play important roles in inhibiting the carcinogenic process. The phytochemicals that are believed to be cancer preventives generally possess one or more common biological properties — induction of phase I or II detoxification enzymes, modulation of phase I and other enzyme activities, antioxidant activity, electrophile scavenging activity, inhibition of nitrosation, and/or modulation of oncogene or protooncogene expression or function. Change of lifestyle and daily eating habits today may greatly reduce risk of cancer in the future. In this chapter, the influence of intake of certain phytochemicals in fruits and vegetables on carcinogenic processes and risk of cancer is discussed and reviewed.