Over the last several years, there has been increasing interest in turmeric and its medicinal properties. This is partially evidenced by the large numbers of scientific studies published on this topic. Turmeric (Curcuma longa), a flowering plant in the ginger family, is widely used as a food coloring and is one of the principal ingredients in curry powder. Turmeric has long been used in both Ayurvedic and Chinese medicine as an anti-inflammatory, to treat digestive disorders and liver problems, and for the treatment of skin diseases and wound healing. The active ingredient in turmeric is curcumin, which has been the subject of numerous animal studies—but as of yet, very few studies on people—demonstrating various medicinal properties. Curcumin has been shown, for example, to stimulate the production of bile and to facilitate the emptying of the gallbladder. It has also demonstrated in animals a protective effect on the liver, anti-tumor action, and ability to reduce inflammation and fight certain infections.

A relative of ginger, turmeric is a perennial plant that grows 3 to 5 feet high in the tropical regions of Southern Asia, with trumpet-shaped, dull yellow flowers. Turmeric is fragrant and has a bitter, somewhat sharp taste.

The aboveground and underground roots, or rhizomes, are used in medicinal and food preparations. These are generally boiled and then dried, turning into the familiar yellow powder. Curcumin from turmeric, as well as other substances in this herb, have antioxidant properties, which some claim may be as strong as vitamins C and E.

While turmeric has a long history of use by herbalists, most studies to date have been conducted in the laboratory or in animals and it is not clear that these results apply to people. Nevertheless, research suggests that turmeric may be helpful for the following conditions.

Digestive Disorders
(stomach upset, gas, abdominal cramps): The German Commission E (an authoritative body that determined which herbs could be safely prescribed in that country and for which purpose[s]) approved turmeric for a variety of digestive disorders. Curcumin, for example, one of the active ingredients in turmeric, induces the flow of bile, which helps break down fats. In an animal study, extracts of turmeric root reduced secretion of acid from the stomach and protected against injuries such as inflammation along the stomach (gastritis) or intestinal walls and ulcers from certain medications, stress, or alcohol. Further studies are needed to know to what extent these protective effects apply to people as well.

Osteoarthritis
Because of its ability to reduce inflammation, turmeric may help relieve the symptoms of osteoarthritis. A study of people using an Ayurvedic formula of herbs and minerals containing turmeric as well as Withinia somnifera (winter cherry), Boswellia serrata (Boswellia), and zinc significantly reduced pain and disability. While encouraging for the value of this Ayurvedic combination therapy to help with osteoarthritis, it is difficult to know how much of this success is from turmeric alone, one of the other individual herbs, or the combination of herbs working in tandem.

Atherosclerosis
Early studies suggest that turmeric may prove helpful in preventing the build up of atherosclerosis (blockage of arteries that can eventually cause a heart attack or stroke) in one of two ways. First, in animal studies an extract of turmeric lowered cholesterol levels and inhibited the oxidation of LDL ("bad") cholesterol. Oxidized LDL deposits in the walls of blood vessels and contributes to the formation of atherosclerotic plaque. Turmeric may also prevent platelet build up along the walls of an injured blood vessel. Platelets collecting at the site of a damaged blood vessel cause blood clots to form and blockage of the artery as well. Studies of the use of turmeric to prevent or treat heart disease in people would be interesting in terms of determining if these mechanisms discovered in animals apply to people at risk for this condition.

Cancer
There has been a substantial amount of research on turmeric's anti-cancer potential. Evidence from laboratory and animal studies suggests that curcumin has potential in the treatment of various forms of cancer, including prostate, breast, skin, and colon. Human studies will be necessary before it is known to what extent these results may apply to people.

Roundworms and Intestinal worms
Laboratory studies suggest that curcuminoids, the active components of turmeric, may reduce the destructive activity of parasites or roundworms.

Liver Disease
Animal studies provide evidence that turmeric can protect the liver from a number of damaging substances such as carbon tetrachloride and acetominophen (also called paracetamol, this medication, used commonly for headache and pain, can cause liver damage if taken in large quantities or in someone who drinks alcohol regularly.) Turmeric accomplishes this, in part, by helping to clear such toxins from the body and by protecting the liver from damage.

Bacterial Infection
Turmeric's volatile oil functions as an external antibiotic, preventing bacterial infection in wounds.

Wounds
In animal studies, turmeric applied to wounds hastens the healing process.

Mosquito Repellent
A mixture of the volatile oils of turmeric, citronella, and hairy basil, with the addition of vanillin (an extract of vanilla bean that is generally used for flavoring or perfumes), may be an alternative to D.E.E.T., one of the most common chemical repellents commercially available.

Eye Disorder
One study of 32 people with uveitis (inflammation of the uvea, the middle layer of the eye between the sclera [white outer coat of the eye] and the retina [the back of the eye]) suggests that curcumin may prove to be as effective as corticosteroids, the type of medication generally prescribed for this eye disorder. The uvea contains many of the blood vessels that nourish the eye. Inflammation of this area, therefore, can affect the cornea, the retina, the sclera, and other important parts of the eye. More research is needed to best understand whether curcumin may help treat this eye inflammation.

Turmeric is commercially available in the following forms:

• Capsules containing powder
• Fluid extract
• Tincture

Bromelain enhances the absorption and anti-inflammatory effects of curcumin, the best studied active ingredient of turmeric; therefore, bromelain is often formulated with turmeric products.

Pediatric

While turmeric may be helpful for the treatment of inflammatory conditions in children, appropriate doses have not yet been established. Until more information is available, consider adjusting the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of turmeric for this child would be 1/3 of the adult dosage.

Adult

The following are doses recommended for adults:

• Cut root: 1,500 to 3,000 mg per day
• Dried, powdered root: 1,000 to 3,000 mg per day
• Standardized powder (curcumin): 400 to 600 mg, 3 times per day
• Fluid extract (1:1) 30 to 90 drops a day
• Tincture (1:2): 15 to 30 drops, 4 times per day

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Turmeric and curcumin are considered safe when taken at the recommended doses. However, extended or excessive use of curcumin may produce stomach upset and, in extreme cases, ulcers. (Note: normal therapeutic doses of turmeric protect from ulcers – see earlier discussion – but, at very high doses, it may induce ulcers. This is why it is very important to stick with the recommended dose of this herbal remedy.) Turmeric should not be taken by those who have been diagnosed with gallstones or obstruction of the bile passages without explicit direction from a qualified practitioner.

While pregnant women needn't avoid foods containing turmeric, its use as a medicinal herb is not recommended during pregnancy because the effects are not fully known. Studies in pregnant rats, mice, guinea pigs, and monkeys suggest that it is safe for those animals, but safety in pregnant women has not been tested.

If you are currently being treated with any of the following medications, you should not use turmeric or curcumin in medicinal forms without first talking to your healthcare provider.

Blood-Thinning Medications
Although no scientific reports have documented a bleed or other adverse interaction, turmeric, taken in medicinal doses may theoretically increase the blood thinning effects and, therefore the risk of bleeding from, drugs such as warfarin and aspirin.

Non-Steroidal Anti-inflammatory Drugs (NSAIDs)
Turmeric has shown protection in animals from the development of ulcers due to this class of medications. NSAIDs include indomethacin, ibuprofen, and many other drugs that are often prescribed for pain and inflammation, such as that of arthritis.

Reserpine
Turmeric protected animals from increased gastric secretions (secretions in the stomach that can lead to damage along the walls of this organ) from reserpine used for high blood pressure.

Ammon HPT, Wahl MA. Pharmacology of Curcuma longa. Planta Medica. 1991;57:1-7.

Arbiser JL, Klauber N, Rohan R, et al. Curcumin is an in vivo inhibitor of angiogenesis. Mol Med. 1998;4(6):376-383.

Asai A, Miyazawa T. Dietary curcuminoids prevent high-fat diet-induced lipid accumulation in rat liver and epididymal adipose tissue. J Nutr. 2001;131(11):2932-2935.

Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Integrative Medicine Communications; 2000:379-384.

Curcuma longa (turmeric). Monograph. Altern Med Rev. 2001;6 Suppl:S62-S66.

Dorai T, Cao YC, Dorai B, Buttyan R, Katz AE. Therapeutic potential of curcumin in human prostate cancer. III. Curcumin inhibits proliferation, induces apoptosis, and inhibits angiogenesis of LNCaP prostate cancer cells in vivo. Prostate. 2001;47(4):293-303.

Dorai T, Gehani N, Katz A. Therapeutic potential of curcumin in human prostate cancer. II. Curcumin inhibits tyrosine kinase activity of epidermal growth factor receptor and depletes the protein. Mol Urol. 2000;4(1):1-6.

Gescher A J, Sharma R A, Steward W P. Cancer chemoprevention by dietary constituents: a tale of failure and promise. Lancet Oncol. 2001;2(6):371-379.

Heck AM, DeWitt BA, Lukes AL. Potential interactions between alternative therapies and warfarin. Am J Health Syst Pharm. 2000;57(13):1221-1227.

Kawamori T, Lubet R, Steele VE, et al. Chemopreventive effect of curcumin, a naturally occurring anti-inflammatory agent, during the promotion/progression stages of colon cancer. Cancer Res. 1999;59:597-601.

Kim MS, Kang HJ, Moon A. Inhibition of invasion and induction of apoptosis by curcumin in H-ras-transformed MCF10A human breast epithelial cells. Arch Pharm Res. 2001;24(4):349-354.

Kiuchi F, Goto Y, Sugimoto N, Akao N, Kondo K, Tsuda Y. Nematocidal activity of turmeric: synergistic action of curcuminoids. Chem Pharm Bull. 1993;41(9):1640-1643.

Kulkarni RR, Patki PS, Jog VP, Gandage SG, Patwardhan B. Treatment of osteoarthritis with a herbomineral formulation: a double-blind, placebo-controlled, cross-over study. J Ethnopharmacol. 1991;33(1-2):91-95.

Lal B, Kapoor AK, Asthana OP, et al. Efficacy of curcumin in the management of chronic anterior uveitis. Phytother Res. 1999;13(4):318-322.

Luper S. A review of plants used in the treatment of liver disease: part two. Altern Med Rev. 1999;4(3):178-188; 692.

Mehta K, Pantazis P, McQueen T, Aggarwal BB. Antiproliferative effect of curcumin (diferuloylmethane) against human breast tumor cell lines. Anticancer Drugs. 1997;8(5):470-481.

Nagabhushan M, Bhide SV. Curcumin as an inhibitor of cancer. J Am Coll Nutr. 1992;11(2):192-198.

Phan TT, See P, Lee ST, Chan SY. Protective effects of curcumin against oxidative damage on skin cells in vitro: its implication for wound healing. J Trauma 2001;51(5):927-931.

Pizzorno JE, Murray MT. Textbook of Natural Medicine. New York, NY: Churchill Livingstone; 1999:689-692.

Ramirez-Tortosa MC, Mesa MD, Aguilera MC, et al. Oral administration of a turmeric extract inhibits LDL oxidation and has hypocholesterolemic effects in rabbits with experimental atherosclerosis. Atherosclerosis. 1999;147(2):371-378.

Rao CV, Rivenson A, Simi B, Reddy BS. Chemoprevention of colon carcinogenesis by dietary curcumin naturally occurring plant phenolic compound. Cancer Res. 1995;55(2):259-266.

Robbers JE, Tyler V. Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press; 1999:73-74.

Sharma RA, Ireson CR, Verschoyle RD. Effects of dietary curcumin on glutathione S-Transferase and Malondialdehyde-DNA adducts in rat liver and colon mucosa: relationship with drug levels. Clin Cancer Res. 2001;7:1452-1458.

Stoner GD, Mukhtar H. Polyphenols as cancer chemopreventive agents. J Cell Biochem Suppl. 1995;22:169-180.

Tawatsin A, Wratten SD, Scott RR, Thavara U, Techadamrongsin Y. Repellency of volatile oils from plants against three mosquito vectors. J Vector Ecol. 2001;26(1):76-82.

Verma SP, Salamone E, Goldin B. Curcumin and genistein, plant natural products, show synergistic inhibitory effects on the growth of human breast cancer MCF-7 cells induced by estrogenic pesticides. Biochem Biophys Res Commun. 1997; 233(3): 692-696.

White L, Mavor S. Kids, Herbs, Health. Loveland, Colo: Interweave Press; 1998:41.