Turmeric has many purported health benefits. Does science back any of them up?

At the end of 2019, it was reported that turmeric, a spice that was once only known to Southeast Asia, had racked up $328 million in annual U.S. sales as a dietary supplement. It's only increased in popularity in the years since as many supplement companies have heavily marketing its health benefits. Some of those benefits are exaggerated or unproven, but others are backed by science. 

"Turmeric's main active component, curcumin, makes it a potential treatment for numerous health conditions," says Denise Millstine, MD, women's health and integrative medicine specialist at Mayo Clinic in Arizona.

But she and other experts say that turmeric needs to be researched further and that there are some known negative side effects from taking too much of the supplement. 

What is turmeric?

A member of the ginger family, turmeric, also known as Curcuma longa, is a flowering plant whose rhizomes (roots) appear similar to the rhizomes of ginger − but with a yellowish-orange color instead of brown. Grated, sliced or peeled in its raw form or dried and ground into a powder, turmeric is a culinary spice that's used extensively in Indian cooking especially, giving foods both flavor and color. It's commonly added to soups, tandoori chicken, rice and curry, and has become a popular enhancement in roasted vegetables and egg scrambles.

Turmeric has also been used as a traditional Indian medicine for centuries and is widely available today as a supplement in the form of both powder and capsules. 

What is turmeric good for?

Though the National Center for Complementary and Integrative Health notes that the health effects of turmeric supplementation on certain medical conditions, "remain uncertain," turmeric does have properties known to be beneficial. For instance, as with other colorful plant-based foods, turmeric is rich in phytonutrients (powerful antioxidants) that are known for protecting one's body from free radicals such as sunlight or air pollution and for shielding cells from damage. "Turmeric may also aid digestion, improve brain function, and support healthy skin," explains Lisa Young, PhD, an adjunct professor of nutrition at New York University and author of "Finally Full, Finally Slim."

What's more, the aforementioned active component of turmeric, curcumin, is known to "decrease and relieve some symptoms of mild arthritis, such as joint pain and joint inflammation," says Jessica Sepel, BHlth, a clinical nutritionist and founder of JSHealth. Turmeric may also improve heart health "as it reduces bad cholesterol while increasing good cholesterol," explains Young.

And the curcumin within turmeric may also have cancer-fighting properties, though again, such research is ongoing. "Some studies suggest that curcumin may have anticancer properties by inhibiting the growth of cancer cells and preventing the formation of new blood vessels in tumors," says Jen Messer, a nutrition consultant and registered dietitian at Jen Messer Nutrition.

Is it OK to take turmeric daily?

But it isn't all good news as many such advantages are still being studied and turmeric has some known negative side effects. "While turmeric is safe to consume, too much of it can cause diarrhea, nausea and headache," explains Young. Eating turmeric may also slow down blood clotting due to its anticoagulant properties, "which can be beneficial for some but dangerous to others," adds Young. 

Millstine notes that though she agrees that "turmeric is generally safe," there are other potential side effects to be mindful of. "The biggest risk I encounter with turmeric in my practice is interactions with other medications," she explains. And she says that some forms of the plant may also cause heartburn.

While there is no standard established dose of turmeric to take daily, "The World Health Organization has determined an acceptable daily intake of turmeric powder as 1.4 milligrams per pound of body weight when turmeric powder is used as a spice in cooking," explains Messer. She adds that most research indicates that turmeric's supplement form should be kept between 500 and 2,000 milligrams daily, "but an effective dose may vary on the condition being treated." 

"As with all herbal dietary supplements, there can be risks associated with consumption," says Sepel. "Therefore, I always recommend checking in with your health professional to ensure that it suits your individual needs." 

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