If you switched from a mainstream toothpaste like Crest to a so-called “natural” toothpaste, grab the tube and check the ingredient list now.
If you see peppermint oil, tea tree oil, spearmint oil, wintergreen, clove oil, or cinnamon oil, your “natural” toothpaste may be disrupting your oral microbiome.
You likely made the switch to avoid harsh chemicals and to choose gentler, more natural products. That intention is understandable. But essential oils are antimicrobial by design — they’ve been used for centuries in wound care and cleaning because they kill microbes effectively. The issue is that these compounds do not distinguish between microbes that protect your mouth and those that contribute to disease.
Some essential oils have potency comparable to chlorhexidine, the strong antimicrobial dentists prescribe after surgery. Brushing with such ingredients twice daily exposes your oral ecosystem to powerful, non-specific antimicrobial pressure.
Why that matters
The common idea that a product “kills bad bacteria but spares good bacteria” is misleading when it comes to the oral microbiome. Your mouth hosts more than 700 microbial species, and most are context-dependent — the same organism can be benign in a balanced ecosystem and associated with disease when the community shifts.
Oral health depends on preserving a stable, functional microbial ecosystem rather than eliminating specific species. Essential oils act through broad mechanisms — disrupting membranes and metabolic pathways — which means they reduce microbial diversity and alter community interactions. Repeated, indiscriminate antimicrobial exposure can destabilize that ecosystem.
When the microbiome is destabilized, opportunistic organisms that tolerate stress can rebound fastest. Those opportunists are often the disease-associated bacteria. That dynamic helps explain why some people who follow good hygiene and diet still experience cavities or gum bleeding: their toothpaste may be undermining their oral ecology.
It’s not only essential oils
A closer look at toothpaste formulations reveals additional concerns — even in brands marketed as “healthy.”
SLS (Sodium Lauryl Sulfate) — the foaming agent in many toothpastes. Foam can feel like a sign of cleanliness, but SLS strips the protective mucosal lining of the mouth. Clinically, SLS use is associated with sloughing of cheek cells and an increased incidence of canker sores. SLS is a strong detergent used in industrial cleaners, yet many people apply it inside their mouths twice a day.
Emulsifiers — used to keep ingredients mixed on the shelf, can also disrupt the oral microbiome’s delicate balance.
Endocrine-disrupting ingredients — compounds such as triclosan and certain preservatives can interfere with hormonal systems. These ingredients still appear in some oral care products.
Before you settle on a product, read the ingredient list and ask: Do I understand what each component is doing inside my mouth?
My confession
I’ve written about these issues for years. In 2017 I published an article titled “Essential Oils — The Potentially Unhealthy Ingredient in Your ‘Healthy’ Toothpaste,” presenting the science and studies on how essential oils can affect the oral microbiome.
At that time I still used a toothpaste called Boka because it contained nano-hydroxyapatite, an ingredient I believed was important for remineralization. I acknowledged the tradeoffs: essential oils and SLS were present, but there were few nano-hydroxyapatite options without those additives. That compromise motivated me to develop a different solution.
Fygg is the toothpaste I wished had existed throughout my career. It contains no fluoride, no essential oils, no SLS, no emulsifiers, no detergents, and no known endocrine disruptors. Instead, it focuses on ingredients that promote remineralization while supporting the oral microbiome.
You’ll notice a different feel at first — no tingling or burn and no heavy foam. That sensation many people associate with “clean” comes from irritants like essential oils and SLS. Removing those makes it clear what a toothpaste should actually feel like.
The science supports the approach. A 2025 study in the Journal of Dentistry, conducted at the University of Texas Health San Antonio, compared eight toothpastes for their ability to remineralize early enamel lesions. In that head-to-head test, Fygg achieved roughly double the remineralization of Boka, a statistically significant difference (p < .01), and performed on par with a prescription-strength fluoride toothpaste (5,000 ppm).
I use Fygg with my family — my daughters and grandchildren — and it’s the first toothpaste I’ve felt comfortable recommending without reservation. No tradeoffs, no asterisks.
Further reading and resources
For more context, review articles and resources on essential oils in toothpaste, SLS and canker sores, and alternatives to fluoride-based care. Reading ingredient lists and understanding how formulations affect both enamel and the oral microbiome will help you choose products that support long-term oral health.
Have a wonderful week,
Mark