Historically, ginger has a long tradition of being very effective in alleviating symptoms of gastrointestinal distress. In herbal medicine, ginger is regarded as an excellent carminative (a substance which promotes the elimination of intestinal gas) and intestinal spasmolytic (a substance which relaxes and soothes the intestinal tract). Modern scientific research has revealed that ginger possesses numerous therapeutic properties including antioxidant effects, an ability to inhibit the formation of inflammatory compounds, and direct anti-inflammatory effects A clue to ginger's success in eliminating gastrointestinal distress is offered by recent double-blind studies, which have demonstrated that ginger is very effective in preventing the symptoms of motion sickness, especially seasickness. In fact, in one study, ginger was shown to be far superior to Dramamine, a commonly used over-the-counter and prescription drug for motion sickness. Ginger reduces all symptoms associated with motion sickness including dizziness, nausea, vomiting, and cold sweating.
Safe and Effective Relief of Nausea and Vomiting During Pregnancy
Ginger's anti-vomiting action has been shown to be very useful in reducing the nausea and vomiting of pregnancy, even the most severe form, hyperemesis gravidum, a condition which usually requires hospitalization. In a double-blind trial, ginger root brought about a significant reduction in both the severity of nausea and number of attacks of vomiting in 19 of 27 women in early pregnancy (less than 20 weeks). Unlike antivomiting drugs, which can cause severe birth defects, ginger is extremely safe, and only a small dose is required.
A review of six double-blind, randomized controlled trials with a total of 675 participants, published in the April 2005 issue of the journal, Obstetrics and Gynecology,has confirmed that ginger is effective in relieving the severity of nausea and vomiting during pregnancy. The review also confirmed the absence of significant side effects or adverse effects on pregnancy outcomes.
Anti-Inflammatory Effects
Ginger contains very potent anti-inflammatory compounds called gingerols. These substances are believed to explain why so many people with osteoarthritis or rheumatoid arthritis experience reductions in their pain levels and improvements in their mobility when they consume ginger regularly. In two clinical studies involving patients who responded to conventional drugs and those who didn't, physicians found that 75% of arthritis patients and 100% of patients with muscular discomfort experienced relief of pain and/or swelling.
Arthritis-related problems with your aging knees? Regularly spicing up your meals with fresh ginger may help, suggests a study published in a recent issue of Osteoarthritis Cartilage. In this twelve month study, 29 patients with painful arthritis in the knee (6 men and 23 women ranging in age from 42-85 years) participated in a placebo-controlled, double-blind, crossover study. Patients switched from placebo to ginger or visa versa after 3 months. After six months, the double-blind code was broken and twenty of the patients who wished to continue were followed for an additional six months.
By the end of the first six month period, those given ginger were experiencing significantly less pain on movement and handicap than those given placebo. Pain on movement decreased from a score of 76.14 at baseline to 41.00, while handicap decreased from 73.47 to 46.08. In contrast, those who were switched from ginger to placebo experienced an increase in pain of movement (up to 82.10) and handicap (up to 80.80) from baseline. In the final phase of the study when all patients were getting ginger, pain remained low in those already taking ginger in phase 2, and decreased again in the group that had been on placebo.
Not only did participants' subjective experiences of pain lessen, but swelling in their knees, an objective measurement of lessened inflammation, dropped significantly in those treated with ginger. The mean target knee circumference in those taking ginger dropped from 43.25cm when the study began to 39.36cm by the 12th week. When this group was switched to placebo in the second phase of the study, their knee circumferences increased, while those who had been on placebo but were now switched to ginger experienced a decrease in knee circumference. In the final phase, when both groups were given ginger, mean knee circumference continued to drop, reaching lows of 38.78 and 36.38 in the two groups.
How does ginger work its anti-inflammatory magic? Two other recent studies provide possible reasons.
A study published in the November 2003 issue of Life Sciences suggests that at least one reason for ginger's beneficial effects is the free radical protection afforded by one of its active phenolic constituents, 6-gingerol. In this in vitro (test tube) study, 6-gingerol was shown to significantly inhibit the production of nitric oxide, a highly reactive nitrogen molecule that quickly forms a very damaging free radical called peroxynitrite. Another study appearing in the November 2003 issue of Radiation Research found that in mice, five days treatment with ginger (10 mg per kilogram of body weight) prior to exposure to radiation not only prevented an increase in free radical damage to lipids (fats found in numerous bodily components from cell membranes to cholesterol), but also greatly lessened depletion of the animals' stores of glutathione, one of the body's most important internally produced antioxidants.
A study published in the February 2005 issue of the Journal of Alternative and Complementary Medicine sheds further light on the mechanisms of action that underlie ginger's anti-inflammatory effectiveness. In this research, ginger was shown to suppress the pro-inflammatory compounds (cytokines and chemokines) produced by synoviocytes (cells comprising the synovial lining of the joints), chrondrocytes (cells comprising joint cartilage) and leukocytes (immune cells).
Protection against Colorectal Cancer
Gingerols, the main active components in ginger and the ones responsible for its distinctive flavor, may also inhibit the growth of human colorectal cancer cells, suggests research presented at the Frontiers in Cancer Prevention Research, a major meeting of cancer experts that took place in Phoenix, AZ, October 26-30, 2003.
In this study, researchers from the University of Minnesota's Hormel Institute fed mice specially bred to lack an immune system a half milligram of -gingerol three times a week before and after injecting human colorectal cancer cells into their flanks. Control mice received no -gingerol.
Tumors first appeared 15 days after the mice were injected, but only 4 tumors were found in the group of -gingerol-treated mice compared to 13 in the control mice, plus the tumors in the -gingerol group were smaller on average. Even by day 38, one mouse in the -gingerol group still had no measurable tumors. By day 49, all the control mice had been euthanized since their tumors had grown to one cubic centimeter (0.06 cubic inch), while tumors in 12 of the -gingerol treated mice still averaged 0.5 cubic centimeter-half the maximum tumor size allowed before euthanization.
Research associate professor Ann Bode noted, "These results strongly suggest that ginger compounds may be effective chemopreventive and/or chemotherapeutic agents for colorectal carcinomas."
In this first round of experiments, mice were fed ginger before and after tumor cells were injected. In the next round, researchers will feed the mice ginger only after their tumors have grown to a certain size. This will enable them to look at the question of whether a patient could eat ginger to slow the metastasis of a nonoperable tumor. Are they optimistic? The actions of the University of Minnesota strongly suggest they are. The University has already applied for a patent on the use of -gingerol as an anti-cancer agent and has licensed the technology to Pediatric Pharmaceuticals (Iselin, N.J.).
