The present invention relates to the use of Echinacea as a cancer chemopreventive agent to block the formation of and to detoxify cancer-causing agents, or carcinogens. More particularly, the present invention relates to the induction of phase II enzymes by Echinacea, and specifically by lipid-soluble fractions isolated from Echinacea. The present invention also contemplates a novel method of extracting the desired lipid-soluble fractions from Echinacea.