It’s no wonder fresh ginger tastes pungent. It contains a family of molecules called gingerols that are structurally related to capsaicin, the compound responsible for the hot bite of chiles.
Challenge a cook to spice up a bland dish, and the obvious choice is ginger. No other seasoning combines the zing of a chile with a clean hit of citrus and the sweet bouquet of a spice such as cardamom or cloves. What a gift, then, that ginger comes with a bounteous platter of health benefits.
Derived from the rhizome (or subterranean stem) of Zingiber officinale, ginger is native to the Orient. It’s now grown in virtually all tropical regions and favored in nearly every cuisine and system of folk medicine. Healers use it for nausea, colic, gas, heartburn, ulcers, for motion and morning sicknesses, for coughs, and for osteoarthritis. Want a paradox and a mystery? Ginger helps warm you when you’re chilled, but it’s also sometimes used to reduce fever.
Recent data from researchers suggests that ginger has value in all these situations. Unfortunately, such research, despite the number of studies, has left more questions than answers. A few studies have been conducted using compounds isolated from ginger, such as one or more of the shogaols or gingerols, but most studies use dried ginger powder with an undetermined quantity of active compounds. When the spice is dried or cooked, gingerols are converted to shogaols, so the form of ginger used and the way in which it’s cooked may make a difference. Both fresh and powdered ginger possess healing compounds, but in varying amounts.
That said, you don’t need a research degree to use ginger to chase away mild nausea or a case of the chills—or to tell you whether you find it delicious. Below is a brief summary of the research that does exist to date.
The Nausea Conqueror
Virtually everyone suffers nausea and vomiting at some point. Although scientific studies conflict on the degree to which ginger quells nausea, consensus holds that it reduces the severity and frequency of vomiting in motion and morning sickness, and possibly following minor surgery and chemotherapy.
Two studies conducted on rough open seas demonstrated ginger’s effectiveness in preventing motion sickness. One involved eighty Danish navy cadets. None of those who ate 1 g of powdered ginger before sailing got seasick, but five of the forty placebo-treated cadets became nauseated. In the second study, performed on tourist volunteers on a Norwegian whaling excursion, 80 percent of those who took no drug became seasick, but less than 10 percent of those who ate ginger four hours prior to the trip had symptoms. Fewer than 25 percent of ginger-treated passengers felt any motion-related distress. However, investigators in another study that used a rotating chair claimed that ginger was ineffective in preventing motion sickness. It’s probably that the studies conducted in real-sea situations furnished more relevant data.
More than half of all women suffer morning sickness in the first trimester of pregnancy. A Danish study suggests that ginger may help those patients suffering extreme nausea. Seventy percent of the study’s participants reported diminished symptoms when they took 250 mg of ginger powder four times daily. Whether ginger is effective in mild to moderate cases remains to be researched.
Another occasion to use ginger’s anti-nausea powers is before surgery. Two studies indicate that 1 g of ginger, eaten prior to laparoscopic surgery, may help with post-procedure nausea. In one of the trials, 51 percent of placebo-treated women suffered nausea while only 28 percent of ginger-treated women did. In the second study, 41 percent of placebo-treated women suffered nausea while only 21 percent of the women who took ginger had symptoms.
Ginger may one day be used to soothe nausea brought on by chemotherapy. In an animal study, a crude extract of ginger prevented vomiting in dogs treated with cisplatin (a chemotherapeutic agent). This suggests that one or more compounds contained in ginger may eventually be helpful in relieving nausea during chemo treatments, though human trials have yet to be done.
Hope For Ulcers, Arthritis
Five studies from Japanese labs and one conducted in Saudi Arabia suggest that compounds isolated from ginger may inhibit the formation of ulcers due to use of nonsteroidal anti-inflammatory drugs (NSAIDs). The studies were conducted on experimental conditions in laboratory animals; the compounds included gingerol and shogaol (see “Where ginger gets its bite,” at left). But the amounts of fresh or dried ginger that would be needed to achieve these results in humans have not been determined.
Danish research has shown that long-term ginger consumption may reduce arthritic conditions, and in some cases radically so. Of fifty patients suffering from rheumatoid arthritis, 75 percent of them experienced marked pain relief, while only 11 percent got no relief. And half of the twenty-eight patients with osteoarthritis also got marked relief with ginger. Unfortunately, the studies measured self-reported findings and weren’t regulated with regard to dosage. The amounts of ginger that patients self-administered varied from about 3 g of powdered ginger to 50 g of fresh ginger per day. So the exact effective dose isn’t clear.
If you suffer from either osteo- or rheumatoid arthritis, consult your health-care provider before adding ginger to your treatment regimen. Be aware that it took several months of treatment before the patients in the Danish studies experienced a high level of relief.
Effects On The Heart
Compounds in ginger may affect two facets of heart disease—cholesterol metabolism and platelet function.
The spice appears to act on cholesterol in two ways: by promoting its excretion and by inhibiting the oxidation of LDL cholesterol, the so-called “bad” cholesterol, that triggers the inflammatory response that ultimately produces clots.
Rats fed the human equivalent of 1 teaspoon of powdered ginger per day showed a threefold increase in the activity of the enzyme controlling the conversion of cholesterol to bile acids, which is the excreted form of cholesterol. Although this doesn’t mean that ginger has the same effect in humans, the reduction in cholesterol oxidation has been demonstrated in both animals that were specially bred to have high LDL cholesterol, and in test-tube experiments.
Platelets are involved in the progression of heart disease because they are attracted to damaged fatty plaques in coronary arteries. At those sites, the platelets release a compound called thromboxane, which in turn triggers a cascade of events that can eventually produce a life-threatening blood clot. Numerous studies have shown that several compounds found in ginger inhibit two enzymes responsible for the production of thromboxane.
Although no studies have attempted to correlate high ginger consumption with reduced rates of heart disease, the evidence clearly supports the inclusion of tasty ginger in a heart-healthy diet. As always, contact your doctor with any questions about potential interactions between ginger and prescription drugs.
For Additional Reading
Bordia, A., et al. “Effect of ginger (Zingiber officinale) and fenugreek (Trigonella foenum–graecum) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease.” Prostaglandins, Leukotrienes and Essential Fatty Acids 1997, 56(5): 379–384.
Ernst, E., and M. H. Pittler. “Efficacy of ginger for nausea and vomiting: A systematic review of randomized clinical trials.” British Journal of Anaesthesia 2000, 84(3): 367–371.
Fuhrman, B., et al. “Ginger extract consumption reduces plasma cholesterol, inhibits LDL oxidation and attenuates development of atherosclerotic apolipoprotein E-deficient mice.” Journal of Nutrition 2000, 130(5): 1124–1131.
Guh, J. H., et al. “Antiplatelet effect of gingerol isolated from Zingiber officinale.” Journal of Pharmacy and Pharmacology 1995, 47(4): 329–332.
Pearson, D. “Inhibition of endothelial cell-mediated oxidation of low-density lipoprotein by rosemary and plant phenolics.” Journal of Agricultural and Food Chemistry March 3, 1997, 45: 578–582.
Cornelia Carlson holds a Ph.D. in biochemistry and is an avid grower and user of herbs. She writes frequently for Herbs for Health and is the author of The Practically Meatless Gourmet, (Berkley, 1996). She writes from her home in Tucson, Arizona.