Nontoxic and Nonorgan Specific Cancer Preventive Effect of Panax ginseng C. A. Meyer

Panax ginseng C. A. Meyer has been recognized as non-toxic mysterious tonic in the Orient. The prolonged administration of red ginseng extract inhibited the incidence and also proliferation of pulmonary tumors induced by various chemical carcinogens. Statistically significant anticarcinogenic effects were observed in powders and extract of 6 year-dried fresh ginseng, 5 and 6 year-white ginseng and 4, 5 and 6 year-red ginseng by newly established 9 week medium-term anticarcinogenicity test using benzo[a]pyrene (BP). In case-control studies, odds ratios (OR) of the cancer of lip, oral cavity and pharynx, larynx, lung, esophagus, stomach, liver, pancreas, ovary, and colorectum were significantly reduced. On the type of ginseng, the ORs for cancer were reduced in fresh ginseng extract intakers, white ginseng extract intakers, white ginseng powder intakers, and red ginseng intakers. In cohort study with 5 years follow-up conducted in ginseng cultivation area, ginseng intakers had a decreased relative risk (RR) compared with non-intakers. The RRs of ginseng intakers were decreased in gastric cancer and lung cancer. These findings strongly suggest that Panax ginseng C. A. Meyer in non-toxic and non-organ specific cancer preventive effects against various cancers. Ginseng should be recognized as a functional food for cancer prevention, and that further studies for the identification of its active components, mechanism of action and clinical interventions should undertaken with worldwide collaboration.