Bioactive substances, also called phytochemicals, have been identified in fruits, vegetables and other crops in addition to vitamins and minerals. Conclusions about effects of phytochemicals on human are miscellaneous, but data showing preventive actions against tumor initiation and growth and other diseases predominate.
Epigallocatechin gallate, the phytochemical from green tea, has been tested in the Department of General Biology and Genetics of 3rd faculty of Medicine, Charles University. Results of experiments confirm the preventive effects of this phytochemical against a mutagenicity of carcinogenic substances.