Getting to the root of the ginseng matter
Erica asks: What are the different types of ginseng and their health benefits?
Wynnie says: Ginseng is one of the most popular herbal supplements in the world, a cure-all which has been used in the prevention and treatment of all types of illnesses for centuries. There are several varieties available, but the American (Panax quinquefolius), Korean/Asian (Panax ginseng) and Siberian (Eleutherococcus senticosus) varieties are the most common.
Technically, Siberian ginseng belongs to a different genus to Asian or American ginseng and doesn't contain the same active ingredients. Both Asian and American ginseng contain substances called ginsenosides which give ginseng its medicinal properties.
American and Asian ginseng roots look like human bodies, with shoots that resemble arms and legs. The Chinese name for this herb is jen shen, which means 'man root'. Both types are fleshy, while the roots of Siberian ginseng are woody and wrinkled. Siberian ginseng only takes a year to grow, while Panax varieties need five to nine years before the roots can be harvested.
For thousands of years, herbalists have used Asian ginseng to treat all kinds of ills, from stress and asthma to cancer. Traditionally, Siberian ginseng has been used to prevent colds and flu, and increase energy, while Native Americans used American ginseng to treat headaches, fever and indigestion.
Most studies deal with Asian ginseng - there is evidence that it may boost the immune system; reduce the risk of some cancers, such as liver, stomach and lung; temporarily reduce stress; and promote well-being and improved mental performance. Its ability to improve mental function seems to increase when taken with ginkgo biloba.
Research has also been done into the effectiveness of ginseng to improve mood and boost physical endurance, as well as treat heart disease, type 2 diabetes, fatigue, high blood pressure, and other conditions, although there are no conclusive results yet.
Some users experience side effects including rashes, nosebleeds, diarrhoea, loss of appetite, anxiety, depression and insomnia.
For adults, the dosage depends on the form of ginseng - whether extract, fresh root fluid extract or dried. There are currently no guidelines for the safe use of ginseng for children and teens.
Breakfast: Granola with milk; water
Lunch: Pizza, bread or rice dish with vegetables, fruit salad; water
Dinner: Spaghetti bolognaise, mashed potato/potato cakes with cheese and bacon, or rice with chicken and broccoli, carrots or cucumber
Drinks: 3 glasses of milk, 5-6 glasses of water
Exercise: 1 hour ballet a week, cross-country training once a week, 30 minutes cycling every day
Wynnie Chan is a British-trained nutritionist. If you've got a question for her or would like to be featured in this column, e-mail firstname.lastname@example.org