This is This Is Now A Thing, where we check out the science behind new health phenomena.
The thing: A $9.95 bottle of Juice Generation cold-pressed juice mixed with two teaspoons of activated charcoal. Here, that means the pitch-black powder of heated coconut shells, but activated charcoal can also be made from sources like wood or coal. Also called activated carbon, activated charcoal is incredibly porous and adsorbent. (That's not a typo—it's a word that means a wide range of molecules and chemicals stick to it.) That last quality makes it useful in all kinds of contexts, from water purification to gas masks to an application in clinical emergencies like overdoses or poisonings.
Dr. Maged Rizk, a gastroenterologist at Cleveland Clinic, uses activated charcoal during poisonings to limit the body's absorption of the toxin. “It’s black,” he says of the charcoal he administers to patients. “It’s this really nasty looking drink. You have them swallow it, and you hope they vomit.” Charcoal's rather gruesome use as a hospital drink aside, the ingredient has recently popped up in a more glamorous place: the juice world.
Juice Generation founder Eric Helms saw a glut of beauty products like face masks and pore strips touting activated charcoal as a "detoxifying" ingredient, and he knew many of his customers drank green juice in hopes that it would improve their skin. "If it had charcoal in it, it would be sort of kicking it up a level," he says. It's now the company's best-selling line.
The hype: Healthy glowing skin, better breath, improved digestion and hangover help. “Just basically drawing toxins out of your body for improved organ function,” says Helms. “I think that there’s benefits and I think a lot of people feel the benefits,” Helms says.
The research: Activated charcoal has been used for centuries in the form of biscuits and supplements for digestive issues. So we know it’s probably not going to hurt you, says Dr. Kent Olson, medical director of the San Francisco Poison Control System and clinical professor of medicine and pharmacy at the University of California, San Francisco. He often uses activated charcoal to treat poisonings and even wrote a paper about the stuff—“Activated Charcoal for Acute Poisoning: One Toxicologist’s Journey”—in the Journal of Medical Toxicology. “Generally we think of charcoal as being inert and not having any chemicals in it,” he says, so it shouldn’t cause poisoning.
But there's very little research to back up its use in average people and over a long period of time. Juice Generation declined to cite any research backing up the health benefits of charcoal. ("If you have questions that skew in that direction, please consult medical professionals," their PR representative told me.) But based on the research out there, there's no way to know what charcoal binds to and what it leaves alone—making it difficult to know whether drinking charcoal juice might flush out the nutrients you are drinking it for in the first place. The experts TIME spoke with said there's little if any evidence for the health benefits of drinking activated charcoal unless you've been poisoned.
A lack of research doesn't necessarily mean the claims aren't true, of course. The gastroenterologist Rizk points out that there's not a lot of pharmacological incentive to fund a study about natural carbon. "People anecdotally swear by it for a lot of these different things," Rizk says. "But the studies haven’t been done."
Charcoal's powerful binding abilities may have an unwanted side effect: “The problem with charcoal is that it’s non-specific. It’ll bind to anything it finds adsorbable,” Olson says. “That could include toxins as well as nutrients." In fact, you don't actually want to get rid of all your body's impurities, he says. "Remember that might include vitamins and amino acids and other things you actually need in your diet," he says. If you eat charcoal with your kale, you might be unwittingly depriving yourself of its nutrients.
And that hangover cure claim? It's unlikely, since charcoal doesn't bind to alcohol all that impressively, Olson says. You'd have to drink about twice the amount Olson gives during poisonings to bind to the amount of alcohol in one beer, he says. And while he can't say for sure, he does say this: “My intuition is there’s nothing here other than the possibility of taking good things out of your system at the same time.”
The taste: Eric Helms knows how to make green juice taste good. Charcoal, he says, was a different story. “That was actually a bigger hurdle for us: trying to have a drink with activated charcoal that people wouldn't gag on.” He acknowledges that it looks a bit off-putting, but we’ve got to hand it to him: the juices really do taste delicious. The black one tastes like a not-too-sweet lemonade; the grey one reminds us of a slightly nutty milkshake; the green one tasted just like a really good green juice.
The bottom line: Despite the clear lack of health evidence, this won’t be the last you see of charcoal-infused foods. Helms says Juice Generation's activated drinks outsell all of their other products. Competing juice companies have their own charcoal lines, too, and a restaurant in Los Angeles is even adding activated charcoal to its cocktail list.
Getting rid of toxins, it turns out, isn't always evidence-based—but it sure is proving to be popular.