Ginseng is a slow-growing, short plant with fleshy roots and is classified in three ways, depending on how long it is grown: fresh, white or red.

Fresh ginseng is harvested before 4 years, white ginseng is harvested between 4–6 years and red ginseng is harvested after 6 or more years.

American and Asian ginseng vary in their concentration of active compounds and effects on the body. It is believed that American ginseng works as a relaxing agent, whereas the Asian variety has an invigorating effect

Some studies have shown that components in ginseng, like ginsenosides and compound K, could protect the brain against damage caused by free radicals

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