Not only is ginger (Zingiber officinale) one of the most popular of all the spices but is also of the top five antioxidant foods (American Journal of Clinical Nutrition, July 2006). Numerous studies investigating ginger’s medicinal properties have also shown it to be effective in conditions such as motion sickness and the prevention and treatment of diseases such as Alzheimer’s disease, cancer, cardiovascular disease, diabetes, inflammatory diseases and stomach ulcers.
Research has shown ginger to have effects against the following conditions:
Two of ginger’s most important antioxidants, curcumin and gingerol, have been shown to inhibit and even reverse the deposition in the brain of the amyloid plaques that are associated with Alzheimer’s disease. Moreover, zingerone, another of ginger’s antioxidants, neutralizes the powerful oxidant, peroxynitrite, which has also been implicated as an aggravating factor in Alzheimer’s and other neurodegenerative diseases.
Several phytochemicals found in ginger have demonstrated strong anticancer activities in both laboratory and clinical studies. While ginger’s anti-tumorigenic effects have yet to be fully understood, they are thought to involve the following mechanisms:
ANTI-INFLAMMATORY: Cancer is often associated with inflammatory processes and ginger’s potent anti-inflammatory activity reduces the risk of inflammation-induced malignancy. Ginger is an effective COX-2 inhibitor, curtailing the activity of potentially damaging COX-2 enzymes, the overproduction of which may cause harm to several tissue types.
CANCER CELL DEATH: The pungent vanilloids, gingerol and paradol found in ginger, are very effective in killing cancer cells. They achieve this both by direct cytotoxic activity against the tumour and indirectly by inducing apoptosis in the cancer cells. Reducing tumour initiation and growth: The phytochemical zerumbone antagonises the processes of both tumour initiation and promotion. It does this by inducing antioxidant enzymes and by weakening the pro-inflammatory signalling pathways associated with communication between cancer cells.
PREVENTS DNA DAMAGE: Melatonin is an antioxidant produced by the body that is also found in some plants, such as ginger. It has the valuable property of being able to access most parts of the body, including brain and nervous tissue, and protects DNA against carcinogenic free-radical damage.
ANTIBACTERIAL: Ginger can eliminate all strains of Helicobacter pylori, the bacteria that are the principal cause of stomach cancer.
CARDIOVASCULAR DISEASE AND CHOLESTEROL
Ginger has been shown to lower dangerously high cholesterol and triglyceride levels, while raising the levels of beneficial HDL. These lipid-modulating effects are partly due to the inhibition of fat absorption from the intestines. In addition, ginger’s cardioprotective effects are enhanced by its ability to reduce platelet stickiness and in so doing further reduce the risk of heart attacks and thrombotic strokes.
Ginger’s long-valued role as a treatment for arthritis and other inflammatory conditions has now been substantiated by a number of scientific studies that show how it is involved in several anti-inflammatory mechanisms. It is a strong inhibitor of COX-2 enzymes, pro-inflammatory cytokines and prostaglandins that are all important components of the inflammatory response. Abnormal tissue inflammation occurs when an excess of prostaglandins, cytokines and COX-2 enzymes are released by cells in joint tissue. The more of these molecules that are released, the more inflammatory cells and chemicals are attracted to the joints where they cause pain and damage to the joint surfaces. These substances are integral to inflammatory mechanisms that can involve many tissue types, as well as the condition known as chronic systemic inflammation.
The hydrochloric acid found in the stomach is a powerful defence against ingested pathogens and rapidly destroys almost all organisms that are taken in with food. Helicobacter pylori, however, is an unusually resilient bacterial species that thrives in the hostile, extremely acidic environment of the stomach. Once established, this bacteria causes a range of problems including indigestion, esophagitis, gastritis, stomach and duodenal ulcers, and stomach cancer. Ginger has traditionally been used as a treatment for stomach ailments, and it has recently been shown to kill all nineteen pathogenic Helicobacter pylori species. The regular ingestion of ginger should help to kill these dangerous bacteria before they become established, and thereby pre-empt the need for antibiotics which destroy many valuable intestinal bacteria, in addition to their intended targets.
Although there has been relatively little investigation into the antidiabetic properties of ginger, promising early studies show that it can increase insulin sensitivity. This suggests that, in all likelihood, it is a valuable prophylactic spice against this disease.
Ginger has a dual antiobesity effect. The phytochemicals gingerol and shogaol increase the metabolic rate and thus help to “burn off” excessive fat and also suppress the absorption of calorie-dense dietary fats from the intestines.
Ginger is a source of a large number of important antioxidants that, amongst other activities, reduce lipid oxidation by enhancing the activities of crucial internally produced antioxidants, such as superoxide dismutase. Melatonin, in particular, is not only a highly effective free-radical scavenger itself, but also stimulates production of the main antioxidant enzyme of the brain, glutathione peroxidase.
Ginger’s prominent role in traditional medical systems have been validated by contemporary research. As is the case with most spices, its preventive effects are enhanced when taken with other spices as there are synergistic effects between the medicinally active compounds that occur in this food group.