Charcoal toothpaste has been pegged as a natural teeth whitener in recent years.
Endorsed by influencers celebrities including Nicole Scherzinger, and sold at Holland & Barrett and Boots, its proponents suggest the dental treatment removes stains from teeth while providing a non-abrasive whitening solution.
However, a new review suggests the toothpaste is actively damaging to teeth.
This is because they don’t contain fluoride, a component essential for battling tooth decay.
The review, published in the British Dental Journal, examined 50 different charcoal toothpastes – of which just eight contained fluoride.
What’s more, even out of those eight toothpastes that do contain fluoride, it might be ineffective because charcoal inactivates fluoride.
Some 96% of these toothpastes also claimed to have whitening and stain removing properties – but none contained a sufficient amount of bleaching agent for this to be the case, according to the review.
Several other claims were also disproved, including teeth strengthening (claimed by 30% of the toothpastes tasted), antibacterial or antiseptic properties (44%) and detoxification (46%). None of these claims are proven, according to the review.
“Not all charcoal toothpastes are the same and some could potentially be causing lasting damage to a person’s teeth,” said Dr Linda Greenwall, lead author of the study and member of the British Dental Bleaching Society, who conducted the research.
“Toothpastes should contain fluoride to have additional health benefits for the teeth,” she added.
“The most worrying aspect about the marketing of charcoal pastes and powders appears to be a strong emphasis on the benefits which appeal to consumers, which have yet to be disproved.
“This ‘scientifically claimed until proved wrong’ approach is favoured over substantiated, evidence-based promotion.”
Dr Lisa and Dr Vanessa Creaven, certified dentists and founders of Spotlight Whitening, tell Yahoo UK they agree with the review’s findings.
“Charcoal toothpaste is absolutely damaging to the teeth, charcoal is an extremely abrasive ingredient which permanently damages the outer layer of the enamel surface,” they said.
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“If you looked at the tooth under a microscope following the use of charcoal you would see a mottling or pitting of the outer layer of the enamel surface which leads to over time and with continued use causes increased discolouration of the tooth surface.
“In reality, using a charcoal toothpaste to whiten teeth is counter-intuitive, the more you use a charcoal-like toothpaste the more roughened the outside surface of the tooth which means the less likely a tooth is to shine and whiten.
“We would recommend a peroxide containing the product to chemically lighten the teeth, this does not cause damage to the outside layer of tooth surface but instead breaks down the extrinsic stains to the tooth surface.”
Looking for a natural alternative to bleach-containing teeth whitening products? Dr. Jerome Sebah, the founder of The Dentist Gallery, suggests baking soda instead.
“If you were to use one ingredient alone to remove stains on your teeth, baking soda would be much better for your oral health rather than charcoal alone as it is an abrasive ingredient,” he advises.
To try it, combine one teaspoon of baking soda with 2 teaspoons of water and brush your teeth with the paste. You can do this a few times weekly.