Food as Medicine Ginger (Zingiber officinale, Zingiberaceae)
|History and Traditional Use|
|Range and Habitat
Ginger (Zingiber officinale) is a tropical perennial herb native to Southeast Asia and widely cultivated in China, India, Nigeria, Australia, Jamaica, and Haiti.1 Its subterranean stem, known as a rhizome, is the edible and medicinal portion of the plant.2 Gingerroot is characterized by its knotted, beige exterior and its yellow interior. The herb features thick, protruding, reed-like3 stems and lanceolate leaves arranged in two vertical columns on opposite sides of the stem.4 Seasonally unfurling from ginger’s leaves are dense, ovoid-shaped flower structures that produce yellow-green flowers with a deep purple, yellow-marked lip.3Ginger plants can have an indefinite spread in tropical climates, though it is susceptible to pests and disease.5 The flavor of ginger is described as sweet and peppery with a prominent spicy aroma due to the presence of gingerols and ketones.6
Phytochemicals and Constituents
Thus far, researchers have identified 115 chemical components in a variety of dried and fresh ginger types.6 The most important phenolic elements of the ginger root are gingerols and their ginger-related composites — paradols, zingerone, and shogaols.6,7 Gingerols are the most abundant constituents of fresh ginger6; the three other phenolic compounds are not as plentiful. When gingerols are cooked or dried, they transform into various bioactive compounds,6 many of which have beneficial antioxidant, anti-inflammatory, and anticarcinogenic properties.7 Research suggests that the optimal dosage of ginger ranges from 250 mg to 4.8 g per day of fresh or dried rhizomes.6,8 Other dosages for ginger intake vary depending on the form in which they are consumed and the purpose for which they are intended.8
Historical and Commercial Uses
In India, ginger has been used as a flavoring agent in food and beverage preparations as well as in traditional Ayurveda medicinal practices.4 Historically, it was regarded as the mahaoushadha (“the great medicine”) among ancient Indians.9 Fresh and dried ginger is used commonly in Ayurvedic medicine for the treatment of ailments such as indigestion, fever, and digestive disorders.8 Fresh ginger is thought to be beneficial in reducing nausea and vomiting due to the presence of shogaol, and dried ginger has been shown to alleviate chronic respiratory conditions.10 In addition, gingerol, the most predominate pungent bioactive compound of ginger, has been reported to stimulate digestive enzymes to help improve gastrointestinally (GI) issues.
In Traditional Chinese Medicine, fresh ginger root (sheng jiang) is considered warm and pungent and recognized for dispersing cold within the stomach, which contributes to the treatment of nausea and vomiting.11 It also is acknowledged as an expeller of exterior cold, quelling inflammation of the stomach and infections related to the cold and flu. Dry ginger (gan jiang) is considered to be more hot and pungent than fresh ginger, and it is responsible for dispersing cold in the spleen region, thereby alleviating ailments such as diarrhea and poor appetite. Quick-fried ginger (pao jiang) is warm and bitter and used to treat symptoms associated with conditions such as dysmenorrhea and diarrhea. Asian cuisine features ginger in a number of dishes for flavoring, including soups, curries, rice dishes, stir-fries, and sauces.12
It is believed that both the Chinese and Indians have used ginger root for medicinal purposes for more than 5,000 years; however, the exact origin is unknown.6 Highly prized for its medicinal properties, ginger was a popular trading commodity exported to the Roman Empire more than 2,000 years ago from India. (Anecdotally, Queen Elizabeth I of England is credited with the creation of the gingerbread man, which evolved into a popular treat consumed during the Christmas holidays.)
Ginger is used commercially in a variety of forms, including, but not limited to, fresh, dried, and candied.6The age of the ginger plant determines its culinary and medicinal use. Young ginger root harvested at five months has not matured and typically has a mild flavor, suitable to be used fresh. At nine months, ginger characteristically has a thick skin and pungent root, from which the volatile oils can be extracted. This material also is used in dried or ground form as a spice and in commercial baking products. Further, ginger is added as a flavoring to a number of different beverages such as ginger ale, ginger beer, and ginger wine.12
A considerable amount of research demonstrates and supports the significant health benefits of ginger. The majority of clinical evidence for ginger’s medicinal properties is related to nausea caused by pregnancy or chemotherapy.13
Three clinical studies have explored the effects of ginger in reducing chemotherapy-induced nausea in young adults and children.14-16 The results from these studies indicated that ginger is effective in decreasing chemotherapy-induced nausea and vomiting. More specifically, one trial indicated that supplementing with ginger (0.5 g to 1.0 g liquid ginger root extract) reduces nausea.16 In a separate study, researchers observed reductions in the prevalence of nausea in patients with breast cancer when 1.5 g powdered dried ginger root was added to an antiemetic therapy following chemotherapy.14
Another clinical study observed the effects of powdered ginger in patients with intra- and postoperative nausea accompanying Cesarean sections.17 The results indicated that episodes of intraoperative nausea were reduced when ginger was administered orally. However, ginger did not have an effect on the overall incidence of intraoperative nausea and vomiting.
Ginger has been explored as a possible treatment for other GI issues such as dyspepsia, gastric emptying, and irritable bowel syndrome (IBS).18-20 The authors of one clinical study tested the effects of ginger on functional dyspepsia and gastric motility.18 The results indicated that ginger increased gastric emptying more rapidly than the placebo; however, ginger did not influence any GI symptoms. Researchers of a related clinical trial examined ginger’s effects on IBS over a period of 28 days.20 The results indicated that the group taking 1 g of ginger had a 26.4% reduction in symptoms.
Studies have shown that ginger may be beneficial for non-GI-related conditions as well. In two separate clinical studies, researchers explored ginger’s mitigating impact on dysmenorrhea. The first study was conducted for a period of three days based on reports of pain experienced during the first two days of menstruation each month.21 The results suggested that ginger had more of an impact on dysmenorrhea symptoms compared to muscle-relaxation exercises. A similar clinical study found that at the end of the study period, 82.85% of the participants in the experimental group reported symptom improvement compared to 47.05% of the participants in the placebo group.22
Three clinical studies have examined the effects of ginger in the treatment of colorectal cancer.7,23,24 As noted, the bioactive compounds of ginger contain antioxidant, anti-inflammatory, and anticarcinogenic properties, which can interfere with pathways responsible for cancer development.7 The results of all three studies demonstrated that an intake of 2 g of ginger root was able to reduce proliferation in the colorectal epithelium. Further, one trial illustrated that ginger simultaneously increased apoptosis (normal, programmed cell death) and differentiation.7 Ginger also exhibited an anti-inflammatory effect in individuals of normal risk and lowered COX-1 in individuals at higher risk.23,24
Other clinical studies have explored the effects of ginger in relation to muscle pain, respiratory distress syndrome, chronic lower-back pain, satiety, migraines, osteoarthritis, and type 2 diabetes.25-32
Macronutrient Profile: (Per 1 tablespoon [6 g] raw ginger)
Secondary Metabolites: (Per 1 tablespoon [6 g] raw ginger)
Good source of:
Magnesium: 3 mg (0.75% DV)
DV = Daily Value as established by the US Food and Drug Administration, based on a 2,000 calorie diet.