Ginger (Zingiber officinale Roscoe) was valued as a spice and medicine of the ancient world long before written history could record its use (Reading 1995).  Thought to have originated in India, the rhizome of the ginger plant has been used as a remedy for morning sickness, nausea, fevers and colds, and as a digestive aid (White 2007).  Ginger was described in early Indian, Chinese, and Greco-Roman medical texts and has always been valued for its medical properties and unique flavor (Blumenthal 2003).  In 2009, ginger sales ranked 18th of all herbal supplements sold in U.S. mainstream retail stores (ABC Website). China and India are the world’s leading producers of ginger today (Blumenthal 2003). 

The historical uses of ginger have varied across cultures.  In traditional Chinese medicine, ginger is indicated for rheumatism, colds and flus, congestion, and even hangovers.  Chinese also consume ginger along with crab as it is considered an antidote and preventative of shellfish poisoning.  In India, ginger is consumed along with “hard to digest legumes” and by pregnant women as a relief for morning sickness (Reading 1995). The primary use of ginger in Western medicine is as an antiemetic for both humans and animals, but additional uses include control of chemotherapy-induced and post-operative nausea, morning sickness, and osteoarthritis (Blumenthal 2003).  Despite its increasing popularity as a health supplement, the primary use of ginger in the U.S. is as a food additive and flavoring. 

Ginger aids digestion by increasing gastric motility, neutralizing acids and toxins, and stimulating bile secretion (Reading 1995).  Some studies have indicated that ginger may be more effective than Dramamine at controlling motion-induced nausea (White 2007). An additional benefit is that ginger exerts its anti-nausea effect directly at the gastric level as opposed to on the central nervous system, where it blocks the nausea feedback loop between brain stem and gastrointestinal tract.  Ginger has also been shown to have anti-inflammatory properties, inhibit thromboxane synthetase, and act as an anti-oxidant (Blumenthal 2003).  Animal and human studies have also implicated ginger as a medicinally valuable antifungal.

Many of the essential oils that give ginger its medicinal properties are concentrated in the thick skin, so the most useful preparations include the tough outer layers of the root-like rhizome (Reading 1995). Ginger can be taken as a tincture or decoction, as powdered dry rhizome, fresh, or candied.  The rhizome contains 40-60% starch, 4-10% oleoresin (pungent, nonvolatile gingerols and dehydrated-gingerols called shogaols), 1-3.3% volatile oils (mostly sesquiterpenes), proteins, lipids, vitamin A, niacin, and minerals (Blumenthal 2003).  The distinctive scent associated with ginger is attributed to the mixture of volatile oils and resin contained in the rhizome (Tyler 1993).  

The molecular constituents of ginger have been largely identified and isolated and some used in isolation in clinical studies with limited success.  The volatile oils that make up one to several percent of the rhizome are composed mainly of zingiberene (34%), β-sesquiphellandrene (12%), β-phellandrene (8%), and β-bisabolene (6%).  These sesquiterpenes contribute to the strong aroma given off by ginger, although gingerols are also a pungent component of the rhizome.  The non-volatile gingerols contained in the oleoresin are presumably derived by a variant of the curcuminoid pathway that uses a fatty acyl thioester in the Claisen reaction that is part of its biosynthesis (Dewick 2009).  Because carbon chain lengths of the acyl thioester can vary, gingerols come in 6- 8- or 10-carbon lengths. 

While there are no confirmed reports of toxicity in humans, large overdoses of ginger may depress the central nervous system or cause cardiac arrhythmias (Tyler 1993).  Caution is also advised for pregnant women taking ginger as a dietary supplement, although this warning is largely anecdotal and no ill-effects have been documented in clinical studies.  A 2005 study investigated the effect or interaction of ginger with blood-thinning medications and found that ginger had no effect on the efficacy of Warfarin or on the ability of blood to coagulate (Jiang et al.).  Ginger is a safe and effective remedy for nausea and a beneficial stimulant of the digestive system. 

American Botanical Council (ABC) Website.  Accessed from http://cms.herbalgram.org/herbalgram/issue86/article3530.html?Issue=86.

Blumenthal, M. The ABC Clinical Guide to Herbs. Austin: American Botanical Council, 2003. Print.

Dewick, P. M. Medicinal Natural Products. Great Britan: CPI, 2009. Print.

Jiang, X., K. Williams, and W. Liauw. 2005. Effect of ginko and ginger on the pharmacokinetics and pharmacodynamics of warfarin in healthy subjects. British Journal of Clinical Pharmacology 59: 425-432.

Reading, G. 1995. Monograph on Ginger. ATOMS 1.

Tyler, V. The Honest Herbal. Binghamton: Haworth Press, 1993. Print.

White, B. 2007. Ginger: an overview.  American Family Physician Website.