The natural plant turmeric has many curative powers but must be used carefully to avoid unintended, even dangerous, side effects. Even though it’s been called a “miracle root,” the “spice of life,” and a promising cure for everything from arthritis to digestive issues to diabetes, turmeric is not a panacea for everyone.
According to Ania Grimone, LAc, CH, an acupuncturist and Chinese herbalist at the Osher Center for Integrative Medicine at Northwestern University, side effects of turmeric tend to be mild and can include nausea, stomach upsets, or an aggravation of GERD symptoms. But some people should avoid turmeric altogether. For example, turmeric is a blood thinner, so those on anticoagulants like warfarin shouldn’t take it. Turmeric is also a uterine stimulant, so it should not be used during pregnancy as it could cause contractions. Others who should avoid turmeric include:
- Breastfeeding mothers (turmeric can stimulate the male-sex hormone androgen)
- Those taking antidiabetic drugs (it lowers blood sugar)
- People who are iron deficient and taking iron supplements (turmeric can impede the absorption of iron)
- Those with gallstones or bile obstruction (turmeric stimulates bile)
A member of the ginger family, turmeric is a low-growing plant native to Southeast Asia. Its active ingredient — curcumin — is found in the root of the plant, which is ground into a bright yellow powder. This powder has been used as a culinary spice and medicinal herb in Asia, and particularly India, for more than 4,000 years. It is best known as an antioxidant and for its anti-inflammatory properties.
In recent years, the use of turmeric has gained popularity in the United States, as consumers explore safer and less costly alternatives to over-the-counter and pharmaceutical medications. According to the American Botanical Council, turmeric was the top-selling herbal supplement in natural and health food stores in 2014, raking in 30.9% more in sales over the previous year.
In her Chicago-based practice, Grimone routinely advises her clients to take turmeric in capsule form as part of an integrative treatment plan to address inflammatory conditions such as back pain and arthritis. On occasion, she may suggest turmeric as part of a preventive strategy for patients concerned with inflammation, immune function, or the risk of heart disease. In this case, Grimone may recommend 500 milligrams of turmeric daily — although, like other practitioners, she prefers to focus on issues such as nutrition, exercise and stress management as a first line of defense.
Alternative to Pain Pills
For her part, Grimone routinely uses turmeric in lieu of NSAIDs, to avoid the side effects of the drugs. Last summer, for example, Grimone was hiking in Europe when she fell and dislocated her kneecap. Reaching for her first-aid kit, Grimone immediately wrapped her knee in an elastic bandage, put on a topical anti-inflammatory cream, and took 4,000 milligrams of turmeric in capsule form. (A therapeutic dose is often 1,000 to 2,000 milligrams a day, but higher doses can safely be tolerated under the supervision of a healthcare provider, she says.) Grimone continued to take about 4,000 milligrams of turmeric a day for the next 7 days and never fully developed inflammation in her knee. Even better, she was hiking the day after her injury — with the aid of walking sticks.
Grimone also administers turmeric to her 15-year-old son, who runs on a cross-country track team. Her son often returns from practice with sore muscles, so Grimone gives him 1,000 milligrams of turmeric twice a day for 2 to 3 days, a dosage based on his weight of 130 pounds. This takes care of his muscle pain and alleviates the need for NSAIDs, she says. When used over a prolonged period of time, NSAIDs can cause side effects such as kidney problems or stomach bleeding and ulcers. At the same time, there seems to be no reliable data on how much turmeric is too much when taken as a supplement.
The Research on Turmeric
Despite the upsurge in the use of turmeric, the National Center for Complementary and Integrative Health (NCCIH) has been slow to fully endorse it. “Preliminary findings from animal and other laboratory studies suggest that a chemical found in turmeric — called curcumin — may have anti-inflammatory, anticancer, and antioxidant properties, but these findings have not been confirmed in people,” it states. Still, the NCCIH continues to fund studies investigating the healing properties of turmeric and has previously subsidized research into these conditions:
Rheumatoid arthritis (RA)
In 2006, Janet Funk, MD, and her colleagues at the NCCIH-funded Center for Phytomedicine Research at the University of Arizona, in Tucson, created symptoms in rats that mimic those of RA symptoms in humans. In a series of experiments, the researchers treated the rats with different preparations and dosages of turmeric extracts. Some of the animals received treatment before developing the RA-like symptoms, and others afterward.
At the time, Dr. Funk discovered that a certain type of turmeric extract appeared to block inflammatory pathways associated with RA in rats, and was most effective when given before the onset of inflammation. Now Dr. Funk is building on these results by recruiting volunteers with RA to participate in a clinical trial. Her research will study the effects of turmeric in people who have RA symptoms despite taking methotrexate, a first-line drug commonly used to treat the condition. The study will be open for enrollment until 2017.
In 2009, the NCCIH partially funded a study that looked at the impact of 2 dietary supplements on Alzheimer’s disease-related chemical processes in the brain. One supplement was a fish oil, rich in the omega-3 fatty acid DHA; the other was curcumin, a component of turmeric. During the study, researchers fed Alzheimer’s disease-model mice a regular or fatty diet. Some of the mice were also given fish oil and/or curcumin supplements. Over a 4-month period, the researchers found that the mice on the high-fat diet showed an increase in Alzheimer’s disease-related chemical processes in their brains; but that the fish oil and curcumin — alone or in combination — counteracted this effect.
The researchers also found that the supplements improved the cognitive performance of the mice on the high-fat diet, as was measured by how well they remembered a maze. Despite these findings, more studies are needed to determine whether curcumin can help humans with Alzheimer’s disease.
Another laboratory study, funded in part by the NCCIH, looked at whether turmeric may have bone-protective properties. Researchers tested two turmeric extracts containing different amounts of curcuminoids in female rats whose ovaries had been surgically removed. (This procedure causes changes associated with menopause, including bone loss.) Researchers injected rats with enriched turmeric extract (94% curcuminoids by weight) or non-enriched turmeric extract (41% curcuminoids), 3 times a week for 2 months. Tests showed that while non-enriched turmeric extract did not have bone-protective effects, curcuminoid-enriched turmeric extract prevented up to 50% of bone loss and preserved bone structure and connectivity. More clinical research is needed to evaluate whether the use of turmeric-derived curcuminoid products can guard against osteoporosis in humans — and particularly in post-menopausal women for whom bone loss is an issue.
In addition to these studies, the American Botanical Council cites in its database 116 clinical trials that are studying the efficacy of turmeric on conditions such as depression, osteoarthritis, psoriasis, metabolic syndrome (a collection of symptoms that can lead to diabetes and heart disease), gingivitis, and digestive disorders, including peptic ulcer, colitis, Crohn’s disease, and irritable bowel syndrome. Ongoing studies are also looking at whether turmeric can minimize the side effects of chemotherapy and radiation in cancer patients. “Botanicals [such as turmeric] don’t have the same financial backing as pharmaceutical drugs, so you’re not always going to get the big clinical studies,” says Randy Horwitz, MD, PhD, chair of the American Board of Integrative Medicine, and medical director for the Arizona Center for Integrative Medicine, in Tucson. “But turmeric has been used in Asia for centuries, and there’s a good safety record to support it.”
As an integrative medicine specialist, Dr. Horwitz uses botanicals and other natural modalities to complement or offset a patient’s need for pharmaceutical drugs. For example, when treating a patient with RA, Dr. Horwitz might draw up a 15-page plan that would include dietary changes, stress-reduction techniques, physical activity, and botanical supplements, in addition to pharmaceutical drugs if needed. “If a patient required a disease-modifying antirheumatic drug [such as methotrexate, sold as Rheumatrex and Trexall] to slow the progression of RA, I would prescribe that,” he says. “But I would also prescribe turmeric — instead of a cox-1 or cox-2 inhibitor — to reduce inflammation.” Cox-1 inhibitors include aspirin, ibuprofen, and naproxen. Cox-2 inhibitors include the drug celecoxib (Celebrex), which has been linked to an increased risk of heart attacks and strokes with long-term use.
In terms of efficacy, turmeric has been shown to be as effective as cox-1 and cox-2 inhibitors in treating arthritis. A Thai study published in 2014 found that curcumin capsules dulled the pain in arthritic knees as well as ibuprofen — but with fewer gastrointestinal side effects. And a small study conducted in India in 2011 found that a combination of two herbal extracts — derived from turmeric root and the Indian plant boswellia — provided more effective knee pain relief than celecoxib (Celebrex) in osteoarthritis patients. “Turmeric is one of our go-to botanicals,” says Dr. Horwitz. “It’s a wonderful compound — safe and well-tolerated.”
Dr. Horwitz does not encourage daily use of turmeric, however, for healthy individuals. “Some patients take turmeric daily for general health, but most take it as they would a pharmaceutical anti-inflammatory,” he notes. “I usually don’t prescribe it as a daily supplement, as I tend to be a minimalist with respect to supplements.”
For consumers who want to use turmeric, for either preventive or healing purposes, experts recommend the following:
Choose supplements carefully
Turmeric can be used to spice up foods or sipped as a tea, as it has been for centuries in Asia. It can be added to curries, soups, casseroles, and many other dishes as part of a healthy diet. But if you don’t like the taste of turmeric or want a more concentrated health boost, go for a supplement, says Dr. Horwitz. Be careful, though, not to overdo it and consume products with turmeric and also take a supplement. “I think it would be hard to ingest ‘too much,’” notes Dr. Horwitz. “But my guess is that ingesting too much of many common spices can cause mild side effects, such as stomach upset, nausea, or diarrhea.”
When shopping for turmeric, look for products that say “standardized for 95% curcuminoids” and list black pepper or piperine among their ingredients. (These items help the body better absorb the turmeric.) Products manufactured with “phytosome technology” — as listed on the label — also have higher absorption rates.
Since botanicals like turmeric are not regulated by the FDA, consumers should look for products certified by the National Sanitation Foundation or the US Pharmacopeial Convention, Dr. Horwitz adds. These groups ensure product and ingredient safety. You can also search for product reviews on ConsumerLab.com, an independent testing company, or ask your healthcare provider for recommendations.
Check your dose
Many turmeric products have a suggested recommendation of 500 milligrams, taken twice daily with food. But there’s no one set amount for everyone, say experts at the Cleveland Clinic. Your dose will depend on your overall health, the condition you are trying to treat (or prevent), and your body’s response to the supplements. Talk with your healthcare practitioner to discuss the right dosage for you. When used as a preventive treatment method or an adjunct to pharmaceutical drugs, turmeric can provide healing properties — much as it has safely for centuries.