Every toothpaste contains an abrasive - a mild abrasive agent that does the mechanical work of cleaning and polishing the tooth surface. It’s one of the least-discussed ingredients in oral care, and one of the most consequential for your enamel.
Kaolin clay is the abrasive Laro chose. Here’s why it matters, and what it means in practice.
What abrasives do in toothpaste
Your teeth accumulate a thin organic film called the pellicle throughout the day - a protein layer that forms naturally on the enamel surface. This film is the primary site of bacterial adhesion and stain accumulation. The abrasive in toothpaste physically disrupts and removes this layer when you brush, taking surface stains and bacteria with it.
Not all abrasives are equal. The key variable is the Relative Dentine Abrasivity (RDA) value - a standardised measure of how abrasive a toothpaste is on dentine (the layer beneath enamel). The World Health Organisation considers an RDA of 250 or below acceptable for daily use; for reference, most mainstream whitening toothpastes have RDA values between 70 and 150. Some ‘advanced whitening’ products sit at 200 or above.
Over time, highly abrasive products contribute to enamel wear - particularly in combination with acidic foods and drinks, or for anyone who brushes with significant pressure. The enamel you have is the enamel you keep; it doesn’t regenerate.
Why kaolin clay
Kaolin is a naturally occurring hydrated aluminium silicate mineral, formed by the weathering of feldspar rocks. It’s one of the softest abrasives available for toothpaste formulation, with an RDA value typically well below 50. It cleans and polishes effectively while being exceptionally gentle on enamel and dentine.
It’s also inert and chemically stable, meaning it doesn’t interact with other actives in the formula and doesn’t leave residue on tooth surfaces. And because it’s naturally mined and minimally processed, it fits comfortably within a clean formulation ethos.
How kaolin compares to other common abrasives
Hydrated silica
Hydrated silica is the most widely used abrasive in mainstream toothpastes. It’s generally safe and effective, but its RDA value varies considerably - manufacturers can adjust the particle size and concentration to achieve different abrasivity levels. A low-silica product and a high-silica product look the same on an ingredient list. Hydrated silica appears in Laro’s formula in a mild concentration, working alongside kaolin rather than as the primary abrasive.
Calcium carbonate
Calcium carbonate is a natural abrasive (it’s the main component of chalk) with a good safety profile and a secondary benefit: it’s mildly alkaline, which helps neutralise acid in the mouth and supports remineralisation. It also appears in Laro’s formula as a gentle complement to kaolin.
Aluminium hydroxide
Used in some natural toothpastes as a fluoride-free abrasive. Gentle RDA profile, generally considered safe.
Baking soda (sodium bicarbonate)
Very low RDA, mild antimicrobial properties, alkaline. Widely used in natural toothpastes. Not in Laro’s current formula, but worth knowing about.
The Laro approach to polishing
Laro’s whitening formula combines three mechanisms: kaolin clay for gentle physical polishing, bromelain (a natural pineapple enzyme) for enzymatic stain dissolution - which removes the protein matrix that stain chromogens bind to - and hydroxyapatite for remineralisation of the enamel surface. The result is a low-RDA product that achieves its whitening effect without depending on aggressive abrasion.
This matters particularly for anyone with enamel sensitivity, existing enamel erosion, or who has been advised by their dentist to use a gentle toothpaste. It also matters for anyone who simply wants their oral care to work with their teeth rather than against them over the long run.
→ Explore Laro’s Naturally Whitening Toothpaste - kaolin clay, bromelain, hydroxyapatite, and xylitol, in an SLS-free formula.