Author: Winston Craig, MPH, PhD, RD.
Turmeric (Curcuma longa), a perennial shrub which belongs to the ginger family, has long been regarded as an important spice in Asian cuisine. The Chinese name that is given to turmeric is jianghuang, which means yellow ginger.
Today, turmeric is cultivated throughout the Indian subcontinent, Southern China, Indonesia, and parts of Africa. It is usually harvested from February to April. The rhizome (the tuber-like root) is cut in pieces, boiled for 5 to 10 minutes, and then dried in the sun.
The Golden Touch
Ground turmeric has long been used as a yellow food coloring agent, a natural dye, and as a spice. Its warm spicy taste and golden, yellow color does much to enhance the quality of a meal. Turmeric can be used to provide a rich, natural yellow color for mashed tofu, rice, salad dressings, puddings, egg and cheese dishes. It is also a major ingredient in curry powders, and has been used to accentuate the flavor of pepper.
Turmeric is considered safe in the amounts commonly used in foods. Turmeric carries a GRAS status by the FDA, which means it is Generally Recognized As Safe to use as a food additive.
In addition to being an important culinary spice, the dried rhizomes of turmeric also have a long history of medicinal use. Traditionally, turmeric has been used for a variety of purposes. It has found use as an appetite stimulant, a digestive aid, a general tonic, as well as for treating diarrhea, dyspeptic complaints, flatulence, and gallbladder complaints. It is also commonly used as an anti-spasmodic in different ethnic communities.
The German Commission E has approved the use of turmeric for its bile-stimulating action, for its anti-inflammatory activity, and in the treatment of digestive complaints.
Turmeric is widely used in the Indian medical system and in traditional Chinese medicine. It has found use externally in ointments and lotions for the treatment of wounds, ringworm, eczema, and inflammations. In Indian medicine, turmeric has a long history of use as an anti-inflammatory agent. Specifically, it has been used in the treatment of arthritis. The volatile oil of turmeric (which is rich in sesquiterpenoids) and the yellow pigments in turmeric are both partly responsible for its anti-inflammatory activity.
Gold Means Protection
The yellow-orange color of turmeric is derived from curcumin, a bright yellow, phenolic pigment. Curcumin is an antioxidant which is considerably more powerful than vitamin E. It has anti-mutagenic activity, as well as the ability to inhibit the growth of certain cancers.
The anti-tumor activity of curcumin is possibly due to its ability to inhibit topoisomerase enzyme activity and protect DNA strands from breakages. The latest research shows that turmeric can suppress the development of stomach, breast, colon, lung and skin tumors.
The starch found in the rhizomes of turmeric contains special polysaccharides (called arabinogalactans) which enhance immune function by stimulating white blood cells to action. Turmeric also possesses some anti-microbial action, and has been used to treat inflammations of the mouth.
It may also play a very minor role in protecting against cardiovascular disease. The yellow pigment curcumin has mild anti-thrombotic activity since it inhibits platelets from clumping together.
How Safe Is It?
Generally speaking, reports of side effects from the use of turmeric are rare. However, persons with gallstones should exercise caution. The use of turmeric is contraindicated in cases of bile obstruction, since it does stimulate the secretion of bile from the gall bladder. Turmeric is also not recommended for use during pregnancy. The excessive oral use of turmeric, or heavy use over an extended period of time, may cause some gastrointestinal disturbances.
Typical dosage is 0.5 to 1.0g capsules used two to three times a day between meals. Tea preparations are not recommended since the active constituents have a low solubility in water. Turmeric should be protected from light, and stored in well-closed glass containers.
Turmeric has had a long history of human use, both internal and external use. It adds a rich golden color and pleasant flavor to food. In addition, it has been used safely and effectively as an anti-inflammatory agent and for the treatment of digestive problems.