Activated charcoal is everywhere — from supplement pills to pressed juices to face masks. But is it safe to use on your teeth?

Proponents say that brushing with activated charcoal removes impurities and buffs away stains from your smile. Charcoal becomes “activated” after it’s been treated by heat and gas to make its surface porous, turning it into a magnet for unwanted particles. It has been around for a long time, used in air filters and even hospitals to treat accidental poisoning or drug overdoses.

According to dentist and spokesperson for the American Dental Association Dr. Kim Harms, however, there is no proof that activated charcoal in toothpaste has any benefit. “There’s no evidence at all that activated charcoal does any good for your teeth. We don’t know about the safety and effectiveness of it.”

Replacing fluoridated toothpaste with activated charcoal may put people at a higher risk for developing decay while abrading the protective enamel shell of their teeth.

“The toothpaste you’re using, from a dentist’s point of view, delivers fluoride,” says Harms. “Fluoride is nature’s cavity fighter and can cut tooth decay by up to 40 percent.” Even in powder form, charcoal is a very hard substance that could eventually strip your dentition of its outer layer. “Like any abrasive, we’re worried about the effects [of charcoal] on the gums and enamel on the teeth.”

Ultimately, there is not enough evidence to support the use of activated charcoal as a toothpaste, especially when compared to the verified benefits of using fluoridated toothpastes. A review of 118 articles about charcoal use in dental products published in September 2017 by the Journal of the American Dental Association concluded that there is insufficient data on the efficacy of charcoal.

Stick to over-the-counter whitening products approved by the American Dental Association to improve the appearance of your smile, or talk to your dental professional about other options to whiten them in a healthy and proven way.