Does turmeric emit a health aura so strong that it's needless to expound upon the specifics? “Everybody knows about the nutritional benefits of turmeric and how its bioavailability increases when you eat it with black pepper, right?” writes Sharon Flynn in the headnote for fermented turmeric in her cookbook Ferment For Good. (...Everybody?, I whisper to myself, bowing my head in shame.)
But when turmeric is in the hands of Instagram-famous lifestyle bloggers, and on the menu of every plant-forward café, suddenly a symbol of a certain kind of prosperity—with its roots in traditional medicine either ignored, obscured, or muddied—well, it can certainly seem that way. Turmeric? Healthy? Why of course!
But what are the health benefits of turmeric—anecdotal or data-driven, passed down between generations or assessed in a science lab?
An Extremely Abridged History, plus a Few Considerations
For thousands of years, turmeric has been used in cooking (600 BCE, according to The New Food Lover’s Companion) and in medicine (in The Spice Companion, Lior Lev Sercarz writes that turmeric ointment was prescribed as far back as 250 BCE in the Sushruta Samhita, an ancient Sanskrit text on medicine and surgery, to mitigate the effects of poison), as a remedy for pain, fatigue, liver problems, wounds, and inflammatory diseases like arthritis, among other ailments.
But turmeric as healer is not “ancient” practice to be skimmed over in history books. In a January article in the New York Times, Tejal Rao describes how, in her Kenyan-Indian family, there was “turmeric for a standard runny nose, the dizzy rush of a fever, the ache of moving away from my best friend. Turmeric for a breakout, a particularly tender, slow-to-heal bruise, the anxieties that kept me awake.”
Rao opens her piece by distinguishing herself from turmeric-toon health bloggers: “I want to tell you that I don’t really believe in the magical properties of turmeric,” she says, “that I was radicalized when I was only a child.” Don't consider Rao among the recently indoctrinated. And while there’s “plenty of research to support turmeric’s antiseptic and anti-inflammatory properties," she concludes that it's “neither a miracle drug nor a supernatural phenomenon. It’s a pungent, gently bitter tropical plant, related to ginger, with bulky, bright orange roots that have been used for centuries in kitchens across Asia, including India, where it is known as haldi.”
To call turmeric "new" or "trendy" is to ignore its long history—and its nuance. Just because turmeric-chai concentrate appeared in my local grocery store in the past week does not mean turmeric (or chai) did not exist before. “The current breathless reverence of the turmeric trend ignores a simple, but important, banality,” Tara O’Brady explains in the Guardian: “We’ve been doing this for generations, above and beyond fashion and not linked to some ephemeral mysticism. This so-called discovery is a framing that excludes the persevering vitality of the culture, one that is the thriving chronicle of its past and still relevant to its present.”
But even acknowledging turmeric’s roots in Ayurvedic practice, and East Asian medicine, too, neglects to recognize the diversity of Indian cuisine. As Food52 staff writer Mayukh Sen argued in his February article, to plaster haldi doodh (the Hindi name for turmeric milk) onto a grand Indian identity is to ignore large groups of Indians who have never encountered that beverage, or who use turmeric as "a cohort and companion to other spices and flavors" rather than as the miraculous medicine Western media advertises it to be.
The Healthy Stuff
Now back to the health claims that have, in large part, contributed to the commercialization and commodification of turmeric: How many of these are anecdotal, and how many are scientifically proven? Which isn't to say that scientific studies, which are expensive to conduct and imperfect in their conclusions, should be the only metric by which we judge “healthfulness.” It is merely to interrogate assertions that are as large in scope as to proclaim that turmeric prevents cancer and Alzheimer’s disease.
To read the nitty-gritty details, jump to the end of the article. But the take-home point, as explained by the University of Maryland Medical Center, is that many of the studies have taken place in vitro and in animals—meaning that the effects might not be the same in humans.
Most of turmeric's health benefits are attributed to curcumin, a member of the curcuminoid group responsible for turmeric’s vibrant orange color (the one you can never seem to get rid of). Curcumin’s been hailed as an antioxidant with anti-inflammatory, antiviral, antibacterial, antifungal, and anticancer activities, with a potential to prevent diabetes, allergies, arthritis, Alzheimer’s disease, and other chronic illnesses.
"a cautionary tale"
But in January, a flurry of articles debunking the health benefits of turmeric turned the tides.
“Forget what you’ve heard: Turmeric seems to have zero medicinal properties,” cried Quartz India. “Everybody Needs To Stop With This Turmeric Molecule,” admonished Forbes. “Turmeric May Be Tasty, But It’s Not a Cure-All,” warned Smithsonian.com.
Throw all your turmeric out the window! The previous assertions of “an ever-growing mountain of evidence [showing] that boldly colored turmeric with its earthy, bitter-gingery taste may offer a plethora of potential health benefits,” as a Pittsburgh Post-Gazette writer put it, seemed to crash-burn (at least in regards to Mount Evidence).
But these articles, while attention-grabbing (and mud-slinging), may have have buried much of the nuance of the paper on which they all drew, The Essential Medicinal Chemistry of Curcumin, published in the Journal of Medicinal Chemistry early this year.
The article, which was the most comprehensive review of the effects of curcumin to date, concludes that the chemical “is an unstable, reactive, nonbioavailable compound and, therefore, a highly improbable lead” for potential pharmaceuticals. While curcumin has been proposed to treat disorders ranging from erectile dysfunction to baldness to cancer to Alzheimer’s disease, “it’s never yielded a proven treatment,” according to a Nature summary of the review article. Despite thousands of research papers, over 120 clinical trials, and more than $150 million of NIH funding in the last two decades, “there’s no evidence [that curcumin] has any specific therapeutic benefits.”
So why has research persisted? It’s because curcumin belongs to a group of deceptive molecules aptly known as PAINS (pan-assay interference compounds) that contribute to misleading screening results by suggesting that specific chemical activity is occurring even when none exists. “Much effort and funding has been wasted on curcumin research,” Gunda Georg, the co-editor-in-chief of the Journal of Medicinal Chemistry, told Nature—and yet her team still fields a steady stream of manuscripts on the topic.
A final twist
Part of the problem, Georg explained to Nature, is that researchers have difficulty narrowing in on the specific chemicals in turmeric that have health properties. Extracts from turmeric contain dozens of compounds in addition to curcumin, which is itself a shorthand name for a group of three closely-related molecules. “In some cases,” Nature reports, “researchers may observe promising biological effects but ascribe activity to the wrong molecule.” (Curcumin is also not easily absorbed by the body, though piperine, found in black pepper, has been shown to increase its bioavailability, which is why you’ll find recommendations, like Flynn’s, for consuming black pepper and turmeric together.)
So while Michael Walters, the co-author of the review that launched a fleet of turmeric skepticism, calls curcumin “a cautionary tale,” he’s not writing off research completely. Rather than focus solely on curcumin, which makes up 3 to 5% of turmeric, new studies should look at turmeric more holistically, he says, as an ingredient or a meal component.
While the January review makes the utility of curcumin supplements alone doubtful, it does not necessarily negate the health benefits of turmeric as a complete structure, when all of its molecules are working together, often in the presence of other foods.
Nor does it detract from the fact that turmeric has been administered in families—to heal burn wounds and soothe anxious brains—for thousands of years, and long before "modern" medicine existed.
a few of the claims and the evidence
- Cancer: According to the University of Maryland Medical Center, the results of research on turmeric’s anti-cancer properties are “still very preliminary.” The website for Memorial Sloan Kettering Cancer Center explains that in rats exposed to cancer-causing substances, those treated with turmeric were protected from colon, stomach, and skin cancers. In the lab, turmeric also prevents the replication of tumor cells when applied directly. Neither of these findings can be applied to the human body.
- Alzheimer’s: Preclinical research suggests that curcumin may benefit the brain (in three case reports, turmeric supplements were associated with improvements in irritability, agitation, and anxiety), but a review conducted by the Alzheimer’s Drug Discovery Foundation and the Cognitive Vitality Program found clinical evidence to be weak, and no trials have tested for dementia prevention.
- Indigestion/Dyspepsia: A double-blind, placebo-controlled study found that turmeric reduced the symptoms of bloating and gas in those suffering from indigestion. Heart disease: While an extract of turmeric lowered cholesterol levels and kept LDL from building up in blood vessels in animal studies, a double-blind, placebo-controlled study found that a dosage of curcumin, the active ingredient in turmeric, did not improve cholesterol levels.
- Bacterial and Viral Infections: Turmeric may kill bacteria and viruses, as suggested by test tube and animal studies, but researchers don’t know whether that would be the same in the human body.
- Inflammation: The University of Michigan refers to curcuminoids, a group of compounds present in turmeric, as having anti-inflammatory properities that may be beneficial in treating Chron’s disease, uveitis (inflammation of the iris), and arthritis.
How do you use turmeric in your everyday life? Does it soothe your stomach, add flavor to your food, dye your clothes? Tell us in the comments below.