Descripton
Ginger, the underground stem, or rhizome, of the plant Zingiber officinale has been used as a medicine in Asian, Indian, and Arabic herbal traditions since ancient times. In China, for example, ginger has been used to aid digestion and treat stomach upset, diarrhea, and nausea for more than 2,000 years. Since ancient times, ginger has also been used to help treat arthritis, colic, diarrhea, and heart conditions. Native to Asia where its use as a culinary spice spans at least 4,400 years, ginger grows in fertile, moist, tropical soil.

Today, ginger root is widely used as a digestive aid for mild stomach upset and is commonly recommended by professional herbalists to help prevent or treat nausea and vomiting associated with motion sickness, pregnancy and etc.

Function:

1、Nausea & Vomittin

Ginger has been shown to reduce the symptoms of motion sickness associated with travel by boat and car. Two double-blind clinical trials have found that ginger may reduce nausea due to anesthesia following surgery, A preliminary trial has suggested ginger may be helpful for preventing chemotherapy-induced nausea.

2、Motion Sickness

Several studies suggest that ginger may be more effective than placebo in reducing symptoms associated with motion sickness. In one trial of 80 novice sailors (prone to motion sickness), those who took powdered ginger extract experienced a significant reduction in vomiting and cold sweating compared to those who took placebo. Similar results were found in a study with healthy volunteers.

3、Pregnancy Related Nausea and Vomiting

At least two studies have found that ginger is more effective than placebo in relieving nausea and vomiting associated with pregnancy. In a small study including 30 pregnant women with severe vomiting, those who ingested 1 gram ginger extract every day for four days reported more relief from vomiting than those who received placebo. In a larger study including 70 pregnant women with nausea and vomiting, those who received a similar dosage of ginger extract felt less nauseous and experienced fewer vomiting episodes than those who received placebo.

4、Nausea and vomiting following surgery

Research has produced mixed results regarding the use of ginger in the treatment of nausea and vomiting following surgery. In two studies, 1 gram of ginger extract before surgery reduced nausea as effectively as a leading medication. In one of these two studies, women who received ginger extract also required fewer nausea-relieving medications following surgery.

5、Anti-inflammation

In addition to providing relief from nausea and vomiting, ginger extract has long been used in traditional medical practices to decrease inflammation. In fact, many herbalists today use ginger to help treat health problems associated with inflammation, such as arthritis, bronchitis, and ulcerative colitis. In a recent study of 261 people with osteoarthritis (OA) of the knee, those who received a ginger extract twice daily experienced less pain and required fewer pain-killing medications compared to those who received placebo.

6、Digestive Tract Tonic

Ginger is considered a tonic for the digestive tract, stimulating digestion and toning the intestinal muscles. This action eases the transport of substances through the digestive tract, lessening irritation to the intestinal walls.Ginger may protect the stomach from the damaging effect of alcohol and non-steroidal anti-inflammatory drugs(NSAIDs)and may help prevent ulcers.

7、Cardiovascular Health and etc.

Ginger also supports cardiovascular health by making blood platelets less sticky and less likely to aggregate.A few preliminary studies suggest that ginger may lower cholesterol and prevent the blood from clotting. Each of these effects may protect the blood vessels from blockage and the damaging effects of blockage such as atherosclerosis. however, more research would be needed to know if these initial study results will ultimately prove helpful for people

Dosage
For prevention or treatment of motion sickness, 500 mg of dried ginger powder extract can be taken one-half to one hour before travel, and then 500 mg every two to four hours as necessary. Children below the age of six should use half of the adult amount. For the treatment of nausea associated with pregnancy, women can take up to 1 gram daily, but should only use ginger for symptomatic relief of nausea and not on an ongoing basis. Ginger may potentially be used for nausea associated with anesthesia or chemotherapy, but only under the supervision of a physician.

SafetyThe use of ginger is a time-honored approach to strengthening the body and treating disease. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

The American Herbal Products Association (AHPA) gives fresh ginger root a class 1 safety rating, indicating that it is a safe herb with a wide dosage range. Side effects associated with ginger are rare, but if taken in excessive doses the herb may cause mild heartburn. The AHPA gives dried ginger root a class 2b rating, indicating that it should not be used during pregnancy.

People with gallstones should consult a physician before taking ginger.

Chemistry
Recent studies have revealed that the pungent constituents, known as gingerols and shogaols1,are responsible for the anti-nausea and anti-vomiting effects of ginger. 
References:
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