It’s time to give charcoal toothpastes the brushoff, according to a new research paper that slams the supposed tooth-whitening products as a “marketing gimmick” that can actually do more harm than good.
The new review published in the British Dental Journal examined 50 charcoal toothpastes to determine whether they lived up to their claims to whiten, strengthen and detoxify teeth. The bottom line: Not only is there no scientific evidence to back up these claims, but also the abrasive quality of charcoal may actually cause tooth decay. Patients with periodontal disease may accumulate charcoal deposits in “pockets” between the teeth and gums, as well, which could discolor them worse than they were before.
This is backed by a 2017 Journal of the American Dental Association study, which analyzed more than 100 articles on charcoal and charcoal-based toothpastes and powders, and found “insufficient clinical and laboratory data” to support their safety or effectiveness, and warned dentists and patients to “be cautious” in using them.
“Not only is it not beneficial, but it’s potentially dangerous,” American Dental Association spokesman Dr. Matt Messina told MarketWatch. “This is where I have to speak out, and where the [dental] profession has to speak out.”
While 96% of the charcoal toothpastes in the U.K. report claimed to have teeth whitening properties, the review noted that bleaching agents are needed for whitening and stain-removing effects — which these charcoal pastes and powders did not have.
“The overall whitening capability definitely has not be proven,” agreed Dr. Bobbi Peterson, an orthodontist in Brooklyn, whose patients ask about the trendy toothpaste a lot. In fact, more than a third (35%) of oral care product users are interested in active charcoal toothpaste for deep cleaning, marketing research firm Mintel told MarketWatch, while 33% are interested in a charcoal toothbrush for antibacterial benefits. And Americans are spending $1.4 billion on over-the-counter whiteners to bleach away the stains from cigarettes, red wine, coffee and natural aging, according to the American Academy of Cosmetic Dentistry.
So dental brands like Colgate, Crest and Burt’s Bees have responded by selling charcoal “whitening” products averaging around $5 to $20. (The companies did not respond to a MarketWatch request for comment by press time.) And celebrity endorsements are making charcoal toothpastes more appealing. Kendall Jenner has formed a partnership with Moon, an oral-care brand that includes a “whitening toothpaste” with activated charcoal for $8.99, for example. “I love it,” she told Allure. Searching #charcoaltoothpaste on Instagram draws more than 36,000 results.
But what’s worse than wasting money on a product that probably won’t work, however, is that the abrasive nature of charcoal may wear down tooth enamel and actually cause teeth to become more stained, and more vulnerable.
Dr. Messina likens it to lightening a hardwood floor: You sand the surface down to the brighter under-layer, but you can only keep doing that until you run out of wood. “Initially, charcoal toothpaste may make teeth look a little whiter because they are abrading the surface enamel of the tooth. But the enamel is only a millimeter-and-a-half thick in certain spots, and your body doesn’t make any more of it. So when it’s gone, it’s gone,” he said. “And the inner layer of the tooth, the dentin layer, is yellow. So rather than whitening your teeth, you could make the color go the other way.”
Plus, “your teeth become more sensitive and more prone to decay and cavities, because you’ve lost that hard, outer protective layer on the teeth,” he added.
Dr. Kelly Giannetti, an orthodontist in Sacramento, agreed. “Charcoal is very abrasive, and warnings include increased caries [aka cavities] and enamel abrasion, which means the charcoal actually removes enamel from the teeth which will never ‘grow’ or regenerate back,” she said.
Also, only 8% of the charcoal toothpastes in the British review contained fluoride, a natural element proven to strengthen teeth and prevent cavities and decay. Indeed, all toothpastes with the American Dental Association’s Seal of Acceptance must contain fluoride. And even those charcoal toothpastes that did contain fluoride could have eliminated the element’s protection, because charcoal can deactivate fluoride, the researchers wrote.
“Charcoal when activated (in higher temperatures, such as body temperature ie the mouth) has an absorptive characteristic. This is good for patients with halitosis (bad breath). It will possibly absorb the bacteria that causes it,” Dr. Peterson said. “(But) this is not so good when it’s combined with agents that help remove plaque or agents that help the enamel resists decay (i.e. fluoride). Charcoal absorbs these agents.”
The American Dental Association recommends speaking with your dentist about your teeth whitening options, which can depend upon the severity of your stains as well as any underlying health issues that could be discoloring your teeth. Or select a whitening toothpaste with the ADA Seal of Approval, which verifies that the toothpaste is safe and lives up to its claims.
But consumers should be wary of teeth-whitening strips, which come with their own risks of burning the gums or damaging that inner dentin layer of your teeth.
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