Charcoal toothpaste is everywhere. Black paste, black bristles, black packaging. The marketing promises whiter teeth, detoxification, and a deep clean. Social media is full of before-and-after shots that make it look like a miracle product.
The clinical picture is less exciting. Here is what we tell patients at our Brisbane clinics when they ask whether charcoal toothpaste is worth using.
What Is Activated Charcoal?
Activated charcoal is a form of carbon that has been processed at high temperatures to create a porous structure. This porous surface gives it adsorptive properties, meaning it can bind to certain substances. It has legitimate medical uses, including the treatment of some types of poisoning in hospital emergency departments.
The leap from "useful in poison control" to "good for your teeth" is where the science gets thin.
How Charcoal Toothpaste Claims to Work
Most charcoal toothpaste brands claim the activated charcoal absorbs stains, toxins, and bacteria from the tooth surface. The idea is that the porous charcoal particles bind to discolouration and lift it away when you spit.
In practice, what charcoal toothpaste primarily does is scrub. The charcoal particles are abrasive. They can remove some surface staining from tea, coffee, and red wine in the same way that any abrasive substance would. A kitchen scourer removes grime from a benchtop. That does not make it a good cleaning product for fine glassware.
The Abrasion Problem
Every toothpaste has an RDA (Relative Dentin Abrasivity) score. This measures how abrasive the paste is against tooth structure. The scale runs from 0 to roughly 250. Toothpastes with an RDA under 70 are considered low abrasion. Most standard fluoride toothpastes sit between 60 and 100.
Many charcoal toothpastes have not published their RDA scores. Independent testing of several popular brands has found RDA values well above 100, and in some cases above 200. This is significant.
High-abrasion toothpaste used daily can:
- Thin the enamel layer. Enamel does not regenerate. Once worn, it is gone permanently.
- Expose dentine. The layer beneath enamel is naturally yellow. Thinning the enamel reveals more of it, making teeth look darker over time. This is the opposite of the whitening effect people are chasing.
- Increase sensitivity. Thinner enamel and exposed dentine means more sensitivity to hot, cold, and sweet foods. See our guide on sensitive teeth for more on this.
- Create surface roughness. Scratched enamel picks up new stains faster than smooth enamel. You may notice teeth staining more quickly after switching to charcoal toothpaste.
The Fluoride Problem
Many charcoal toothpastes do not contain fluoride. Some brands actively market the absence of fluoride as a feature, aligning with wellness trends that frame fluoride as harmful.
Fluoride is the single most evidence-backed ingredient in preventive dentistry. It strengthens enamel, reduces the rate of demineralisation, and promotes remineralisation of early decay. Decades of research across millions of patients support its use. The Australian Dental Association, the World Health Organization, and every major dental body worldwide recommend fluoride toothpaste.
Switching to a fluoride-free charcoal toothpaste means removing a proven protective agent from your routine. For patients who are prone to cavities, this can lead to measurable increases in decay risk.
What the Research Says
A 2017 review published in the Journal of the American Dental Association examined the available evidence on charcoal-based dental products. The authors concluded that there was insufficient clinical or laboratory data to support the safety and efficacy claims of charcoal toothpastes. They noted concerns about abrasivity and the lack of fluoride in most formulations.
A 2019 study in the British Dental Journal found that charcoal toothpastes provided no additional whitening benefit beyond what conventional whitening toothpastes achieved, while carrying higher abrasion risks.
No charcoal toothpaste has received approval or endorsement from the Australian Dental Association.
Book a whitening consultation to discuss safe options
What About Charcoal Powder?
Loose activated charcoal powder, applied directly to the teeth with a wet toothbrush, is even more concerning than charcoal toothpaste. The particle size is uncontrolled, the abrasivity is unpredictable, and there is no fluoride or any other beneficial ingredient. It is an abrasive substance being rubbed directly on enamel.
We have seen patients in north Brisbane present with noticeably worn enamel after months of daily charcoal powder use. The damage is irreversible.
Safer Ways to Address Tooth Staining
If your goal is whiter teeth, there are options with strong evidence and controlled risk profiles:
For surface staining:
- A low-abrasion whitening toothpaste (RDA under 100, containing fluoride) can help maintain brightness between professional cleans.
- Regular check-ups and professional cleaning remove calcified stain that no toothpaste can address.
- Reducing intake of high-stain foods and drinks, or rinsing with water after consuming them, slows stain accumulation. See our stain prevention guide.
For intrinsic colour change:
- Professional teeth whitening using hydrogen peroxide or carbamide peroxide is the most studied and predictable method for changing the actual colour of teeth. It works by penetrating the enamel and oxidising pigment molecules within the tooth structure, not by scrubbing the surface.
- For teeth that do not respond to whitening, porcelain veneers (from $1,200 per tooth) provide a permanent colour and shape change.
How to Choose a Safe Toothpaste
When selecting a toothpaste, look for:
- Fluoride content. At least 1,000 ppm (parts per million) for adults. Most Australian-sold toothpastes meet this threshold.
- ADA endorsement. Products carrying the Australian Dental Association seal have been independently assessed for safety and efficacy.
- RDA under 100 for daily use. Higher-abrasion products should only be used occasionally, if at all.
- Active ingredients that match your needs. Sensitivity? Look for potassium nitrate or stannous fluoride. Gum health? Look for stannous fluoride or triclosan-free antibacterial agents.
For a detailed breakdown, read our guide on which toothpaste to use.
Why Charcoal Toothpaste Is Not Worth the Risk
Charcoal toothpaste is a marketing success and a clinical concern. It can remove some surface staining in the short term, but the abrasion risk, the lack of fluoride, and the potential to make teeth appear darker over time make it a poor choice for daily use.
If you have been using charcoal toothpaste and have noticed increased sensitivity or a change in the appearance of your teeth, it is worth having your enamel assessed. We can check for early signs of wear and recommend a toothpaste that matches your specific needs.
Ivy Dental is in Everton Park and Nundah, open seven days across Brisbane's north side.
