An herb many Americans take to get an energy boost might also help doctors treat one of the most common—and deadly—cancers. Researchers have discovered that ginseng, particularly when heated, may be very effective against colorectal cancer, according to a study in The American Journal of Chinese Medicine.
Colorectal cancer is one of the most common types of cancer in the United States, and among the deadliest. Half of patients diagnosed with colorectal cancer eventually die from the disease, and less than 10 percent of patients with colorectal cancer that has spread will survive more than five years after diagnosis.
Because chemotherapy and other standard treatments aren’t always effective and may have serious side effects, many patients have turned to herbal remedies. Ginseng has been a staple of Asian herbal medicine, and studies have indicated that it might help not only prevent cancer, but also relieve some of the side effects (such as nausea and vomiting) of cancer therapies.
Ginseng comes in Asian and American varieties, both of which contain active compounds called saponins, which are responsible for the herb’s anti-cancer properties. Although Asian ginseng has a long history of use, and research, American ginseng has not been as well studied. Last year researchers at The University of Chicago launched a $6 million effort funded by the National Institutes of Health to investigate the anti-cancer potential of American ginseng.
As part of that study, the researchers treated human colorectal cancer cells with extracts of American ginseng berry and root that had been steam heated. The steamed extracts increased the saponin activity, and halted the cancer cells’ growth by as much as 99 percent. Steaming the Chinese herb notoginseng similarly increased its anti-cancer effect.
Although treatment with ginseng doesn’t work as well as chemotherapy, it might be an effective adjuvant cancer treatment, says study author Chun-Su Yuan, MD, PhD, Director of the Tang Center for Herbal Medicine Research at The University of Chicago. “It could be used together with chemotherapy to increase its efficacy and also to reduce the chemotherapy side effects,” he says. “It possibly could be a single compound that could be a new-generation cancer drug.”
Although ginseng doesn’t have any noticeable adverse effects in moderate doses, when given in larger amounts patients have noted increased heart rate, nausea, headaches, and difficulty sleeping, among other symptoms. The challenge is to determine the optimal dose, and figure out how to deliver ginseng in the most effective way to target the cancer cells without causing significant side effects. Future research should help resolve these issues. “We would like to start human trials in the future,” Dr. Yuan says. “Our initial results were promising.”
Currently researchers are only in the animal testing phase, and Dr. Yuan does not recommend that patients take ginseng supplements for cancer prevention or treatment. Ginseng hasn’t yet been studied well enough for this purpose, and there is no guarantee that the active components Dr. Yuan’s team identified in the study will be in any given bottle of supplements.
If you are interested in taking ginseng be sure to speak with your licensed healthcare practitioner.
Wang Chong-Zhi, Yuan Chun-Su. Potential role of ginseng in the treatment of colorectal cancer. The American Journal of Chinese Medicine. 2008;36:1019-1028.