Ginger is an herb with a complex chemical structure and proven efficacy in treating certain medical conditions. So why don't we know more about it and use it more often?
Actually, many parts of the world have been using this herb for more than 2,000 years -- it is a common additive and medicinal herb in Chinese and Indian cultures.
Over the last 20 years, numerous studies have shown the efficacy of ginger in treating various conditions. In vitro studies suggest that ginger has antiemetic, anti-inflammatory, and hypoglycemic effects and may additionally protect against Alzheimer's disease and cancer.
The best studied effect of ginger is its gastrointestinal properties. Ginger is commonly used to treat various types of "stomach problems," including motion sickness, morning sickness, colic, upset stomach, gas, diarrhea, nausea caused by cancer treatment, nausea and vomiting after surgery, as well as loss of appetite.
How does it work on the GI tract?
The chemicals shogoal and gingerol found in the ginger rhizome are believed to stimulate the flow of saliva, bile, and gastric secretions. Ginger also has been found to suppress gastric contractions and improve intestinal muscle tone and peristalsis. Constituents in ginger are thought to interact with 5HT-3 receptors and may be partially responsible for the antiemetic (antinausea) benefits.
How well does ginger work on various conditions?
Studies have shown that ginger is possibly effective for:
Nausea and vomiting following surgery. Most clinical research shows that taking 1 gram of ginger one hour before surgery seems to reduce nausea and vomiting during the first 24 hours after surgery. One study found ginger reduced nausea and vomiting by 38 percent.
However, ginger might not reduce nausea and vomiting in the period three to six hours after surgery. There is no conclusive evidence, however, about the izziness. Taking ginger appears to reduce the symptoms of dizziness and nausea.
Preventing morning sickness. It should go without saying: Discuss the possible risks with your health-care provider.
Arthritis. There is some preliminary evidence that ginger might be helpful for decreasing musculoskeletal pain in rheumatoid arthritis and osteoarthritis. But studies have shown varying degrees of benefit, possibly because ginger seems to take many months to start working.
Alzheimer's and cancer. Furthermore, an in vitro study shows early evidence that ginger may have therapeutic effects against Alzheimer's disease by protecting neuronal cells from beta-amyloid insult. And finally, in vitro studies and some in vivo studies in mice show that ginger may be effective in preventing the growth of cancer cells, including lung and ovarian cancers.
How do you take ginger?
Ginger products are made from fresh or dried ginger root, or from steam distillation of the oil in the root. The herb is available in extracts, tinctures, capsules, and oils. Fresh ginger root can be prepared as a steeped tea.
Ginger also is a common cooking spice and can be found in a variety of foods and drinks, including gingerbread, ginger snaps, ginger sticks and ginger ale. Usually, however, food sources flavored with ginger contain less than 1 percent ginger.
The therapeutic dose of ginger, generally, should not exceed 4 grams daily.
Judge and Barish-Wreden are medical directors of Sutter Downtown Integrative Medicine program in Sacramento, Calif.