Ginseng root is a traditional herbal remedy that's been used in different places around the world for centuries.
Ginseng is very popular, with the UK market for ginseng products being worth around £8.3 million in 2009.
Fatigue, weakness and exhaustion
Products containing ginseng root have been registered for the medicines regulator MHRA for the temporary relief of fatigue, weakness and exhaustion.
This registration doesn't mean there's scientific proof ginseng works, but it does confirm traditional use and good manufacturing standards.
Ginseng root should not be taken by children aged under 18, women who are pregnant or breastfeeding, or anyone who is allergic to ginseng.
Side effects of ginseng root include skin sensitivity and itching, trouble sleeping, upset stomach, nausea and diarrhoea.
Seek medical advice before starting any herbal remedy in case it causes problems with an existing medicine or condition.
Ginseng may interfere with blood clotting and could increase the risk of bleeding during an operation.
Ginseng has traditionally been used for a number of medical conditions. However, only a fraction of them have been properly researched.
There are several different species of ginseng, including Panax, Asian or Chinese ginseng, and Panax quinquefolius or American ginseng.
Some people use Panax ginseng in the hope that it will help with memory and concentration, but there's no conclusive evidence that it works, according to a systematic review by the Cochrane Collaboration.
Some studies have found that ginseng may help boost the immune system, especially when taken with a vaccine, or by elderly people recovering from an illness, but studies are inconclusive and more research is needed.
Several studies have also shown that ginseng may lower blood sugar levels, which could benefit people with type 2 diabetes. One 2005 study in the American Journal of Chinese Medicine concluded: "both American and Asian ginseng, including root, berry, and leaf demonstrate a significant potential in treating diabetes mellitus." People with diabetes should only take ginseng if recommended by their doctor.
Ginseng has also been studied as a possible way to improve mood and boost endurance as well as help fend off cancer, heart disease, fatigue, erectile dysfunction, hepatitis C, high blood pressure, menopausal symptoms and other conditions. While some of these uses are promising, the evidence isn’t conclusive.
Ginseng food sources
There are no natural food sources of ginseng. Ginseng may, however, be added to energy drinks and foods.