Ginger as a dietary supplement

• DEFINITION: Herbal product promoted as a dietary supplement for specific health benefits.
• PRINCIPAL PROPOSED USES: Morning sickness in pregnancy, motion sickness, postsurgical nausea
• OTHER PROPOSED USES: Atherosclerosis, high cholesterol, immune system benefits, metabolic health, migraine headaches, osteoarthritis, rheumatoid arthritis

Overview

Native to southern Asia, ginger is a perennial that is 2 to 4 feet in length and produces grasslike leaves up to 1 foot long and almost 1 inch wide. Although it is called ginger root in the grocery store, the part of the herb used is actually the rhizome, the underground stem of the plant, with its outer covering (similar to bark) scraped off.

Ginger has been used as food and medicine for millennia. Arabian traders carried ginger root from China and India to be used as a food spice in Ancient Greece and Rome. Tax records from the second century show that ginger was a source of revenue for the Roman treasury.

Chinese medical texts from the fourth century Before the Common Era (BCE) suggest that ginger was used for treating nausea, diarrhea, stomachache, cholera, toothaches, bleeding, and rheumatism. Ginger was later used by Chinese herbalists to treat a variety of respiratory conditions, including coughs and the early stages of colds.

Ginger’s modern use dates to the early 1980s, when a scientist named D. Mowrey noticed that ginger-filled capsules reduced his nausea during an episode of flu. Inspired by this, he performed the first double-blind study of ginger. Germany’s Commission E subsequently approved ginger as a treatment for indigestion and motion sickness.

One of the most prevalent ingredients in fresh ginger is the pungent substance gingerol. However, when ginger is dried and stored, its gingerol rapidly converts to the substances shogaol and zingerone. It remains unknown if any of these substances have medicinal effects.

Uses and Applications

Some evidence suggests that ginger may be slightly helpful for the prevention and treatment of various forms of nausea, including motion sickness, nausea and vomiting of pregnancy (morning sickness), and postsurgical nausea. (Pregnant women and people undergoing surgery should not self-treat with ginger except under physician supervision.)

Scant preliminary evidence suggests that ginger might be helpful for osteoarthritis. One small study suggests that it may be beneficial for high cholesterol. Ginger has been suggested as a treatment for numerous other conditions, including atherosclerosis, migraine headaches, rheumatoid arthritis, ulcers, depression, and impotence; however, there is negligible evidence for these uses.

In traditional Chinese medicine, hot ginger tea taken at the first sign of a cold is believed to offer the possibility of averting the infection. However, there is no scientific evidence for this use.

Scientific Evidence

Nausea. The evidence for ginger’s effectiveness in various forms of nausea remains mixed. It has been suggested that in some negative studies, poor-quality ginger powder might have been used. In general, while most antinausea drugs influence the brain and the inner ear, ginger appears to act directly on the stomach.

Motion sickness. Ginger has shown inconsistent promise for the treatment of motion sickness. A double-blind, placebo-controlled study of seventy-nine Swedish naval cadets at sea found that one gram (g) of ginger could decrease vomiting and cold sweating but without significantly decreasing nausea and vertigo. Benefits were also seen in a double-blind study of thirty-six persons who were given ginger, dimenhydrinate, or a placebo.

However, a 1984 study funded by the National Aeronautics and Space Administration using intentionally stimulated motion sickness found that ginger was no more effective than a placebo. Two other small studies have also failed to find any benefit. The reason for the discrepancy may lie in the type of ginger used or in the severity of the stimulant used to bring on motion sickness.

Nausea and vomiting during pregnancy. Four double-blind, placebo-controlled studies enrolling 246 women found ginger more effective than placebo for the treatment of morning sickness. For example, a double-blind, placebo-controlled trial of seventy pregnant women evaluated the effectiveness of ginger for morning sickness. Participants received either a placebo or 250 milligrams of powdered ginger three times daily for four days. The results showed that ginger significantly reduced nausea and vomiting. No significant side effects occurred.

A minimum of three studies compared ginger to vitamin B6, a commonly recommended treatment for morning sickness. Two studies found them to be equally beneficial, while the third found ginger to be somewhat better. However, because the effectiveness of vitamin B6 for morning sickness is not solidly established (the evidence rests largely on one fairly old study), these findings are of questionable value. Despite its use in these studies, ginger has not been proven safe for pregnant women.

Postsurgical nausea. Although there have been some positive studies, on balance, the evidence regarding ginger for reducing nausea and vomiting following surgery is discouraging. A double-blind British study compared the effects of ginger, placebo, and metoclopramide (Reglan) in the treatment of nausea following gynecological surgery. The results in sixty women indicated that both treatments produced similar benefits compared with placebo.

A similar British study followed 120 women receiving elective laparoscopic gynecological surgery. Whereas nausea and vomiting developed in 41 percent of the participants given placebo, in the groups treated with ginger or metoclopramide, these symptoms developed in only 21 and 27 percent, respectively. Benefits were also seen in a double-blind study of eighty people. A study of sixty people found marginally positive results. However, a double-blind study of 108 people undergoing similar surgery found no benefit with ginger compared with placebo. If ginger is effective for postsurgical nausea, the effect is very slight.

Other forms of nausea. One study failed to find ginger helpful for reducing nausea caused by the cancer chemotherapy drug cisplatin. In a second study, ginger did not add to the effectiveness of standard medications to treat chemotherapy-induced nausea and vomiting.

Osteoarthritis. A large double-blind study (more than 250 participants) found that a combination of ginger and another Asian spice called galangal (Alpinia galanga) can significantly improve arthritis symptoms. This study was widely publicized as proving that ginger is effective for osteoarthritis. However, the study design makes it impossible to draw any conclusions about the effectiveness of the ginger component of the mixture. Ginger alone has been tested only in a handful of small double-blind studies, and they had contradictory results.

As the twenty-first century progressed, ginger was investigated for further health benefits. A review published in 2019 showed ginger decreased the waist-to-hip ratio in dieters, suggesting its effectiveness as a weight loss supplement. A review of studies published in 2022 found individuals taking ginger showed a reduction in fasting blood sugar levels in patients with diabetes. A study published the same year showed ginger could lower LDL cholesterol while raising HDL cholesterol. Ginger was also being studied for its potential to improve cognition, fight infections, and treat indigestion and menstrual pain.

Dosage

For most purposes, the standard dosage of powdered ginger is 1 to 4 g daily, divided into two to four doses per day. To prevent motion sickness, one should begin treatment one or two days before a trip and continue it throughout the period of travel.

Safety Issues

Ginger is on the GRAS (Generally Recognized As Safe) list of the US Food and Drug Administration as a food, and the treatment dosages of ginger are comparable to dietary usages. No significant side effects have been observed.

Like onions and garlic, extracts of ginger inhibit blood coagulation in test-tube experiments. European studies with actual oral ginger taken alone in normal quantities have not found any significant effect on blood coagulation. However, it is still theoretically possible that a weak anticoagulant could amplify the effects of drugs that have a similar effect, such as warfarin (Coumadin), heparin, clopidogrel (Plavix), ticlopidine (Ticlid), pentoxifylline (Trental), and aspirin. One fairly solid case report appears to substantiate these theoretical concerns: the use of a ginger product markedly (and dangerously) increased the effect of an anticoagulant drug closely related to Coumadin. However, a double-blind study failed to find any interaction between ginger and Coumadin, leaving the truth regarding this potential risk unclear. Finally, the maximum safe doses of ginger for pregnant or nursing women, young children, or persons with severe liver or kidney disease have not been established.

Important Interactions

Ginger could amplify the effects of strong blood-thinning drugs such as Coumadin, heparin, clopidogrel, ticlopidine, pentoxifylline, and aspirin. Also, ginger might increase the risk of bleeding problems.

Bibliography

Alizadeh-Navaei, R., et al. "Investigation of the Effect of Ginger on the Lipid Levels." Saudi Medical Journal, vol. 29, 2008, pp. 1280-84.

Ensiyeh, J., and M. A. Sakineh. "Comparing Ginger and Vitamin B6 for the Treatment of Nausea and Vomiting in Pregnancy." Midwifery, vol. 25, 2009, pp. 649-53

“Ginger.” NCCIH, Dec. 2020, www.nccih.nih.gov/health/ginger. Accessed 23 Nov. 2024.

“Ginger Benefits.” Johns Hopkins Medicine, www.hopkinsmedicine.org/health/wellness-and-prevention/ginger-benefits. Accessed 23 Nov. 2024.

Leech, Joe. “11 Proven Health Benefits of Ginger.” Healthline, 13 Aug. 2024, www.healthline.com/nutrition/11-proven-benefits-of-ginger. Accessed 23 Nov. 2024.

Matthews, Anne, et al. "Interventions for Nausea and Vomiting in Early Pregnancy." Cochrane Database of Systematic Reviews, 8 Sept. 2015, onlinelibrary.wiley.com/doi/10.1002/14651858.CD007575.pub4/full. Accessed 23 Nov. 2024.

Takahashi, M., et al. "Clinical Effectiveness of KSS Formula, a Traditional Folk Remedy for Alcohol Hangover Symptoms." Journal of Natural Medicines, vol. 64, 2010, pp. 487–91.

Wu, K. L., et al. "Effects of Ginger on Gastric Emptying and Motility in Healthy Humans." European Journal of Gastroenterology and Hepatology, vol. 20, 2008, pp. 436–40.

Zick, S. M., et al. "Phase II Trial of Encapsulated Ginger as a Treatment for Chemotherapy-Induced Nausea and Vomiting." Supportive Care in Cancer, vol. 17, 2009, pp. 563–72.