You use it twice a day. You put it in your mouth. You're supposed to spit it out, but some always gets swallowed. And you've probably never once looked at the ingredient list on the back of the tube.
Most people haven't. The toothpaste category has always had a kind of regulatory halo — it sits adjacent to medicine, it's dentist-recommended, it feels clinical and trustworthy. It must be fine.
But when you actually read what's in most mainstream toothpastes, a different picture emerges. Several common ingredients have legitimate safety questions attached to them. Some are outright banned in food products but permitted in a product you put in your mouth daily. And the packaging — the tube itself — is a plastics disposal problem that most people never think about.
This is what's actually in your toothpaste. And what to use instead.
Ingredient 1: Sodium Lauryl Sulphate (SLS)
SLS is the foaming agent in most mainstream toothpastes. It's what makes the paste lather when you brush. It's also a known irritant.
Clinical studies have linked SLS in toothpaste to increased frequency of aphthous ulcers — the painful mouth ulcers that many people experience regularly without ever connecting them to their toothpaste. A 1996 study in the Journal of Clinical Periodontology found that patients using SLS-free toothpaste experienced significantly fewer ulcers than those using SLS-containing formulations.
SLS is also a surfactant that strips the mucous lining of the mouth — the same mucous membrane we've discussed as a primary absorption surface. Disrupting this barrier isn't a neutral act.
The foam SLS creates is not a functional part of how toothpaste cleans your teeth. It's a sensory signal — a marketing-conditioned association between "lathering" and "clean." Your teeth can be thoroughly cleaned with a non-foaming product. The foam is for you, not for your teeth.
Ingredient 2: Artificial Sweeteners
Most mainstream toothpastes contain saccharin or sorbitol as sweetening agents — to make the paste palatable and encourage people (especially children) to brush longer.
Saccharin's safety record is complicated. It was placed on a US government list of potential carcinogens in the 1970s based on animal studies, later removed when the mechanisms weren't confirmed in humans. The current scientific consensus is that it's probably safe in the amounts found in toothpaste — but "probably safe" in a product used twice daily for a lifetime is a lower assurance than many people would want.
Sorbitol is less controversial but functions partly as a humectant to keep the paste from drying out — and in sensitive individuals can cause digestive disruption if swallowed in quantity, which is relevant in the context of children's toothpaste.
Ingredient 3: Triclosan
Triclosan is an antibacterial agent that was, until recently, present in many mainstream toothpastes — most notably Colgate Total, which contained it for over two decades.
The US FDA banned triclosan from hand soaps in 2016 after manufacturers failed to demonstrate it was safe for long-term daily use and more effective than soap and water. However, it remained permitted in toothpaste (specifically Colgate Total) under a separate regulatory process until Colgate reformulated in 2019.
Triclosan is a known endocrine disruptor — it interferes with thyroid hormone regulation — and has been detected in human blood, urine, and breast milk. It also contributes to antibiotic resistance when released into water systems.
Colgate has removed it from their formula. But triclosan's presence in one of the world's best-selling toothpastes for more than twenty years is a useful illustration of how slowly regulatory safety assessments move relative to long-term exposure risks.
Ingredient 4: Carrageenan
Carrageenan is a thickening agent derived from red seaweed — which sounds natural enough. And in its natural form, it is. But the form used in food and personal care products — degraded carrageenan — has been associated with intestinal inflammation in animal studies and has been classified as a possible human carcinogen by the International Agency for Research on Cancer.
It appears in many "natural" toothpastes as a thickener, often alongside genuinely clean ingredients, which makes it easy to miss. The research on human health effects from degraded carrageenan is contested — some researchers argue the doses in personal care products are too small to matter. But in a product used twice daily for a lifetime, "contested safety" is worth knowing about.
Ingredient 5: Fluoride (The Complicated One)
Fluoride is the ingredient most people actually think about when it comes to toothpaste safety, and it's the most complicated to discuss honestly.
The fluoride used in toothpaste is effective at preventing tooth decay — this is well-established and not seriously contested. The addition of fluoride to municipal water supplies and toothpastes has been credited with a significant reduction in tooth decay rates across the developed world over the last 70 years.
At the same time, fluoride is a substance that has a meaningful toxicity threshold. Fluoride toothpaste carries warnings not to swallow it — relevant for children, who regularly do. High fluoride exposure during tooth development is associated with dental fluorosis (white spots or streaking on teeth). Emerging research on very high fluoride exposure and neurological effects is ongoing, though current dental consensus is that toothpaste-level fluoride is safe when used as directed.
This is genuinely a case where the science supports use at recommended levels, while reasonable questions exist about cumulative exposure in children, and where the individual's risk tolerance and personal values should inform the choice.
Non-fluoride alternatives — hydroxyapatite toothpastes in particular — are backed by a growing body of research supporting their effectiveness in remineralising enamel. They represent a credible alternative for those who choose to avoid fluoride, though the evidence base is currently less extensive than for fluoride.
Ingredient 6: Microplastics in Toothpaste
Beyond the bristles of your toothbrush, the toothpaste itself can be a source of microplastic exposure.
Conventional toothpastes often contain synthetic polymer ingredients used as thickeners, film formers, or abrasives. Carbomer, polyethylene glycol (PEG), and various acrylate copolymers are synthetic polymer compounds that appear regularly in mainstream toothpaste formulations.
These aren't the same as microbeads (which have been banned in many countries), but they are petroleum-derived synthetic polymers introduced into the mouth alongside your toothpaste, twice daily. (More context on bathroom-wide microplastic exposure in our bathroom chemical exposure breakdown.)
The Tube Problem
Even setting aside what's inside the toothpaste, the packaging deserves a mention.
Standard toothpaste tubes are made from a laminated combination of plastic and aluminium — a multi-material structure specifically designed to be flexible, squeezable, and barrier-resistant. It is also, as a consequence of those same design features, essentially impossible to recycle at standard facilities.
The UK alone disposes of around 300 million toothpaste tubes per year. Virtually none are recycled. They go to landfill. The tube you squeezed this morning will outlast you by several centuries.
Compare this to a brand that thinks about packaging from the start. KYND's toothbrush packaging is 100% kraft cardboard — no plastic windows, no synthetic coating, no lamination. The entire box is home compostable. It's a small but meaningful example of what packaging looks like when end-of-life is considered at the design stage rather than added as an afterthought. (For the full breakdown of what "fully biodegradable" actually means.)
What to Use Instead: Cleaner Toothpaste Alternatives
Three credible alternatives, ranked by accessibility:
- Hydroxyapatite (HAp) toothpaste — Hydroxyapatite is a naturally occurring mineral that makes up the majority of your tooth enamel. HAp toothpastes work by remineralising enamel directly, without fluoride. The research is strong and growing — a 2019 meta-analysis found HAp toothpaste comparable to fluoride in cavity prevention for low-caries-risk individuals. Brands like Boka, Risewell, and Davids use it. Often available in aluminium tubes or glass jars.
- Toothpaste tablets — Concentrated solid tabs in recyclable tins or compostable pouches. No plastic tube. Many formulations are fluoride-free and SLS-free. Brands like Bite, Denttabs, and Georganics make well-reviewed options. There's a short adjustment period to the tablet format.
- Natural powder toothpaste — Tooth powders based on bentonite clay, activated charcoal, baking soda, and essential oils. Zero plastic packaging (glass jars). Effective for most people. Not for everyone in terms of texture preference.
When choosing, look for: SLS-free, no artificial sweeteners, no synthetic polymer thickeners, minimal or plastic-free packaging.
The Full Oral Care Picture
The toothpaste is one piece of the puzzle. The bristles are another — and arguably the more urgent one, because what your bristles are made of is being introduced directly into your mouth with every stroke, regardless of what toothpaste you use.
A natural horsehair toothbrush paired with a clean toothpaste formulation is the most comprehensive upgrade you can make to your oral care routine. It's the combination that eliminates synthetic polymers from both the bristle and the paste — the two things touching your teeth and gums every single morning.
That's what an actually clean routine looks like. Not just better branding on the same nylon brush and SLS paste. Genuinely different materials, from the ground up. (And as we explored in our piece on good-enough oral care, "almost natural" isn't the same as actually natural.)
Start with the toothbrush. KYND's natural horsehair bamboo toothbrush 4-pack — no nylon, no synthetic polymers. Available at trykynd.co
References
- Herlofson, B.B. & Barkvoll, P. (1996). Sodium lauryl sulfate and recurrent aphthous ulcers. Journal of Clinical Periodontology.
- FDA (2016). 5 Things to Know About Triclosan. fda.gov
- International Agency for Research on Cancer. Monographs on the Evaluation of Carcinogenic Risks to Humans.
- Limeback, H. et al. (2019). Hydroxyapatite vs fluoride: A meta-analysis. Journal of Dentistry.
- Azoulay, D. et al. (2024). Microplastic release from toothbrushes. Microchemical Journal.