In the study, 340 people who were either being treated for cancer in some form or had just completed their treatment routine, were asked to take a pill every day. Half of the people took a high dose (2000 milligrams) of pure American ginseng while the other half were given a placebo. The study ran for eight weeks and the patients rated their fatigue on a standardized scale with numerical rankings. At the end of the study, the people who had been taking the ginseng pills reported feeling much less fatigue than the others did, ranking their levels as twenty points lower on the numerical scale. Critics of the study cited the fact that ginseng is a known stimulant making the findings a little obvious.
Debra Barton, PhD., the lead researcher and author of the findings warned that ginseng was not for everybody and had to be obtained in its purest form for the study. Commercially available ginseng is processed using ethanol which may be dangerous to those who are fighting breast cancer because some of the compounds become hormone like.
Ginseng has been found to be beneficial in other studies as well. A University of Maryland study showed that ginseng could be used to safely lower the blood sugar levels in people with Type II Diabetes. Another study showed that the natural stimulant could be used to slow or stop the growth of colorectal cancer cells. It has also been used for centuries to reduce the length of common colds and to boost the immune system. None of those studies specified the type of ginseng being studied, however. There are several types of the root including Siberian, Korean and American.
Although natural, ginseng is not without its risks and side effects however. Common side effects include headaches, nausea and vomiting, insomnia and elevated blood pressure. Ginseng also interferes with certain medications and should only be taken with a doctor's approval.
source: http://www.streetarticles.com/cancer/cancer-patients-may-benefit-from-gingseng