A growing body of evidence suggests that chronic low-grade inflammation and oxidative stress may lead to cancer development. These discoveries complement the usual focus of cancer prevention that primarily concentrates on carcinomas, i.e., ectodermal or endodermal (embryonic) tissue-derived cancers, which are more exposed to lifestyle/environment-related risk factors. Based on these findings, cancer preventive strategies can be formulated by using a number of dietary phytochemicals that display inhibitory effects on oxidative stress, inflammation, and other tumor-linked phenomena such as angiogenesis, cell proliferation, and DNA damage. Overall, a positive lifestyle and healthy food habits can reduce cancer risk.