Are the ingredients extracted from fruits and vegetables superior to fruits and vegetables in cancer prevention?

A diet high in fruits and vegetables decreases the risk of various cancers. And recently, several ingredients extracted from fruits and vegetables are observed to have a protective effect against different cancers as well. Many of them have been allowed to enter clinical trial. Due to the fact that these ingredients possess not only a comparatively high purity and quantity, but also a potential economic value, it seems that they are superior to and could replace fresh vegetables and fruits in cancer prevention in the future. Herein, we proposed the hypothesis: the ingredients cannot take the place of fresh fruits and vegetables in cancer prevention.