Turmeric (Curcuma longa) has been used for 4,000 years to treat a variety of conditions. Studies show that turmeric may help fight infections and some cancers, reduce inflammation, and treat digestive problems, and it has gotten a lot of press lately.
But remember several facts when you hear news reports about turmeric. First, many studies have taken place in test tubes and animals, and turmeric may not work as well in humans. Second, some studies have used an injectable form of curcumin, the active substance in turmeric. Finally, some of the studies show conflicting evidence.
Turmeric is widely used in cooking and gives Indian curry its flavor and yellow color. It is also used in mustard and to color butter and cheese. Turmeric has been used in both Ayurvedic and Chinese medicine as an anti-inflammatory, to treat digestive and liver problems, skin diseases, and wounds.
Curcumin is also a powerful antioxidant. Antioxidants scavenge molecules in the body known as free radicals, which damage cell membranes, tamper with DNA, and even cause cell death. Antioxidants can fight free radicals and may reduce or even help prevent some of the damage they cause.
In addition, curcumin lowers the levels of two enzymes in the body that cause inflammation. It also stops platelets from clumping together to form blood clots.
Research suggests that turmeric may be helpful for the following conditions:
Indigestion or Dyspepsia
Curcumin stimulates the gallbladder to produce bile, which some people think may help improve digestion. The German Commission E, which determines which herbs can be safely prescribed in Germany, has approved turmeric for digestive problems. And one double-blind, placebo-controlled study found that turmeric reduced symptoms of bloating and gas in people suffering from indigestion.
Turmeric may help people with ulcerative colitis stay in remission. Ulcerative colitis is a chronic disease of the digestive tract where symptoms tend to come and go. In one double-blind, placebo-controlled study, people whose ulcerative colitis was in remission took either curcumin or placebo, along with conventional medical treatment, for 6 months. Those who took curcumin had a relapse rate much lower than those who took placebo.
Turmeric does not seem to help treat stomach ulcers. In fact, there is some evidence that it may increase stomach acid, making existing ulcers worse. (See "Precautions" section.)
Because of its ability to reduce inflammation, researchers have wondered if turmeric may help relieve osteoarthritis pain. One study found that people using an Ayurvedic formula of herbs and minerals with turmeric, winter cherry (Withinia somnifera), boswellia (Boswellia serrata), and zinc had less pain and disability. But it’s impossible to know whether it was turmeric or one of the other supplements -- or all of them together -- that was responsible.
Early studies suggested that turmeric may help prevent atherosclerosis, the buildup of plaque that can block arteries and lead to heart attack or stroke. In animal studies, an extract of turmeric lowered cholesterol levels and kept LDL "bad" cholesterol from building up in blood vessels. Because it stops platelets from clumping together, turmeric may also prevent blood clots from building up along the walls of arteries. But a double-blind, placebo-controlled study found that taking curcumin, the active ingredient in turrmeric, at a dose of up to 4 g per day did not improve cholesterol levels.
There has been a great deal of research on turmeric's anti-cancer properties, but results are still very early. Evidence from test tube and animal studies suggests that curcumin may help prevent or treat several types of cancers, including prostate, breast, skin, and colon cancer. Its preventive effects may be because it is a strong antioxidant, protecting cells from damage. More research is needed. Cancer should be treated with conventional medications. Don’t use alternative therapies alone to treat cancer. If you choose to use complementary therapies along with your cancer treatment, make sure you tell all your doctors.
Bacterial and Viral Infections
Test tube and animal studies suggest turmeric may kill bacteria and viruses. But researchers don’t know whether it would work in people.
A preliminary study suggests curcumin may help treat uveitis, an inflammation of the eye’s iris. In one study of 32 people with chronic anterior uveitis, curcumin was effective as corticosteroids, the type of medication usually prescribed. More research is needed.
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and may interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care provider.
Turmeric in food is considered safe.
Turmeric and curcumin supplements are considered safe when taken at the recommended doses. However, taking large amounts of turmeric for long periods of time may cause stomach upset and, in extreme cases, ulcers. People who have gallstones or obstruction of the bile passages should talk to their doctor before taking turmeric.
If you have diabetes, talk to your doctor before taking turmeric supplements. Turmeric may lower blood sugar levels, and when combined with medications for diabetes could cause hypoglycemia (low blood sugar).
Although it is safe to eat foods with turmeric, pregnant and breastfeeding women should not take turmeric supplements.
Because turmeric may act like a blood-thinner, you should stop taking it at least 2 weeks before surgery. Tell your doctor and surgeon that you have been taking turmeric.
If you are being treated with any of the following medications, you should not use turmeric or curcumin in medicinal forms without first talking to your health care provider.
Blood-thinning Medications -- Turmeric may make the effects of these drugs stronger, raising the risk of bleeding. Blood-thinners include warfarin (Coumadin), clopidogrel (Plavix), and aspirin, among others.
Drugs that reduce stomach acid -- Turmeric may interfere with the action of these drugs, increasing the production of stomach acid:
- Cimetidine (Tagamet)
- Famotidine (Pepcid)
- Ranitidine (Zantac)
- Esomeprazole (Nexium)
- Lansoprazole (Prevacid)
Diabetes Medications -- Turmeric may make the effects of these drugs stronger, increasing the risk of hypoglycemia (low blood sugar).
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