What is Fluoride?
Fluoride is a naturally occurring mineral that strengthens tooth enamel and helps prevent cavities. Although it has been the subject of public debate, decades of dental research consistently support its safety and effectiveness when used appropriately.
Fluoride is found throughout the environment, including in water, soil, air, and many foods. Chemically, it is the ionic form of fluorine, meaning it naturally binds with other minerals rather than existing on its own. Because of this, humans have been exposed to small amounts of fluoride for as long as we have consumed natural water and food sources.
In dentistry, fluoride is best known for its role in protecting tooth enamel. While fluoride can be ingested, modern dental research shows that its most important effect is topical. When present in saliva after brushing, fluoride works directly on the surface of the teeth to strengthen enamel and reduce the risk of tooth decay—without significantly affecting the rest of the body when used at appropriate concentrations.
How Fluoride Affects Your Teeth
What is tooth enamel?
Tooth enamel is made primarily of a mineral called hydroxyapatite, which is strong but vulnerable to acids produced by oral bacteria. When you eat or drink sugars and carbohydrates, bacteria in dental plaque metabolize them and release acids that lower the pH in the mouth. If the pH drops below a critical level, a process called demineralization begins, which is the first step in cavity formation.⁵
How does fluoride interrupt this process?
Fluoride helps interrupt this process in several important ways. When fluoride is present in saliva at appropriate concentrations, it binds to the surface of enamel crystals, slowing down demineralization caused by bacterial acid. Even when some mineral loss occurs, fluoride also plays a crucial role in remineralization, the natural process by which lost minerals are redeposited into the enamel.⁵
During the remineralization process, fluoride becomes incorporated into the enamel structure, forming a compound known as fluorohydroxyapatite, a modified mineral that is more resistant to acid than the original enamel. Over repeated cycles of acid exposure and repair, the tooth surface becomes stronger and more resistant to acids.⁵
Additionally, fluoride can interfere with the metabolism of cavity-causing bacteria. It inhibits key bacterial enzymes involved in sugar breakdown, reducing acid production within dental plaque. This contributes to a less acidic oral environment, which further protects teeth from decay.⁵
How Brushing with Fluoride Fits Into a Complete Oral Care Routine
Brushing with fluoride is an important part of oral health, but for a complete oral care routine, it is important to take care of the entire mouth.
Interdental cleaning and plaque control
Fluoride strengthens enamel, but it does not remove plaque. Flossing and interdental cleaning are essential for disrupting bacterial buildup between teeth and along the gumline, where toothbrush bristles may not reach.
Tip: Brush after flossing/interdental cleaning and tongue scraping so fluoride and other active ingredients can stay in your mouth and work on the tooth surface. After brushing, spit out excess toothpaste and avoid rinsing with water to help keep those ingredients in place.
Tongue scraping and the oral biofilm
Another important part of a healthy oral care routine is using a tongue scraper to target oral biofilm. Oral biofilm is a thin layer of bacteria, food debris, and dead skin cells that naturally builds up on the tongue’s textured surface and can contribute to bad breath and bacterial spread in the mouth. Gently scraping the tongue once or twice a day helps physically remove this buildup, supporting fresher breath and a cleaner oral environment alongside brushing and flossing. (Read more about oral biofilm here: [link]).
Diet and acid exposure
Diet plays a major role in oral health. Frequent consumption of sugary or acidic foods and drinks increases the risk of enamel erosion. Fluoride helps protect enamel from acid and sugar; it cannot fully counteract constant exposure. Limiting between-meal snacking, reducing sugary drinks, and allowing time between acid exposure gives enamel a chance to recover and remineralize.¹⁰
Why Fluoride Has Become Controversial
Fluoride has been used in dentistry for decades, yet it remains one of the most debated topics in oral health. Much of this controversy does not come from new scientific evidence, but from confusion about dosage, exposure, and how fluoride is meant to be used – especially with children.
Toxicity and proper use
One of the main reasons fluoride has become controversial is that it is often discussed without proper context. Like many substances, including vitamins, minerals, and medications, fluoride is beneficial at proper doses and harmful only at very high ones. Scientific reviews consistently show that fluoride toxicity only occurs at doses far above those encountered through normal use of toothpaste or drinking water.⁵
For context, fluoride can also be ingested through common foods and drinks. For example, brewed tea has been measured to contain around 0.3–1.5 mg of fluoride per cup (one cup of coffee contains 0.22 mg), depending on the type and preparation, which can be similar to or exceed the small amount of fluoride accidentally swallowed from toothpaste during normal brushing (~0.1 mg).⁷
Fluoride is not fluorine
Fluoride is not the same as fluorine. Fluorine is a highly reactive element that does not occur freely in nature, while fluoride is a stable, naturally occurring mineral form. In oral care, fluoride refers specifically to this safe, mineral form used in small amounts to protect tooth enamel.
Is fluoride safe for children?
A significant portion of fluoride-related concern centers on young children, particularly because they are more likely to swallow toothpaste rather than spit it out.⁶
What the Research Actually Shows
Fluoride is safe for children
The evidence indicates that the risk for children is not fluoride contacting the teeth, but how much toothpaste may be swallowed. Dental fluorosis, a cosmetic change in enamel appearance, can occur with long-term excessive intake during tooth development, while acute fluoride toxicity occurs only at doses far above those that can result from normal toothpaste use.²,⁵,⁹
For this reason, children’s toothpaste recommendations account for this by specifying both age-appropriate fluoride concentrations and small, controlled amounts of toothpaste. This allows children to benefit from fluoride’s cavity-preventive effects while minimizing the risk of excessive intake.⁶,⁹
Fluoride-free toothpastes often don’t protect as well as fluoride toothpaste
Research shows that most very low fluoride formulas provide little to no meaningful cavity protection. Some fluoride-free formulas include hydroxyapatite, a mineral naturally found in tooth enamel, which supports remineralization by filling in microscopic surface defects.¹
For this reason, it is recommended that one brushes one's teeth two times daily using toothpaste with a fluoride concentration as follows: ⁵,⁶,⁹
-
6 months - 2 years 1000ppm (rice grain or size of the child’s pinky fingernail)
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2 - 6 years 1000ppm (pea size)
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6 years and over 1450 (1-2cm)
When Fluoride May Not Be the Right Choice
While fluoride is safe and effective for most people, some individuals may choose or need to limit fluoride use due to personal preferences or specific medical considerations. This can include people with advanced kidney disease, certain thyroid conditions, or those advised by a healthcare professional to reduce overall fluoride exposure. In these situations, having effective fluoride-free alternatives, such as hydroxyapatite-based formulations, allows individuals to continue supporting enamel health while aligning with their personal or medical needs.³,⁴
Hydroxyapatite: A Fluoride Alternative for Enamel Remineralization
Hydroxyapatite is the primary mineral that makes up tooth enamel and is used in oral care products to support enamel repair. Research shows that hydroxyapatite particles can bind to demineralized enamel and help fill microscopic surface defects, promoting remineralization.
Clinical studies suggest that hydroxyapatite-containing toothpastes can be comparable to fluoride toothpaste in reducing early caries progression in low-risk individuals, without the risk of fluorosis. However, hydroxyapatite does not form fluorapatite, the more acid-resistant mineral created when fluoride is incorporated into enamel. For this reason, fluoride remains the most well-documented and effective option for cavity prevention, especially for people at higher risk of decay.
Rather than being competitors, fluoride and hydroxyapatite can be complementary: fluoride strengthens enamel by increasing its resistance to acid, while hydroxyapatite helps replenish lost minerals and smooth the enamel surface. Used together, they support both protection and repair. In our Essential Whitening Toothpaste and remineralizing serum in our Whitening Kit, we include both fluoride and hydroxyapatite.¹
So, Is Fluoride Safe and Worth Using?
Based on decades of clinical research, the answer is yes – fluoride is both safe and worth using when used appropriately. When applied topically through toothpaste, fluoride has been shown to strengthen tooth enamel, reduce cavities, and help protect against acid damage.
Concerns about fluoride safety often stem from excessive intake, not daily use. In children, the primary risk is swallowing too much toothpaste during the formative years of tooth development, which can lead to fluorosis. Research shows that this risk can be effectively managed through dose control and supervision, instead of sacrificing fluoride’s cavity-preventive benefits.
When used as part of a comprehensive oral care routine – including regular brushing, flossing, tongue scraping, routine dental care, and a balanced diet – fluoride helps protect and remineralize teeth.
Frequently Asked Questions About Fluoride
“Is fluoride in toothpaste the same as fluoride in drinking water?”
→ Not exactly. Modern research indicates that fluoride’s primary benefit is topical, meaning it acts on the tooth surface through saliva after brushing. Brushing your teeth delivers the fluoride where it is needed, which is why it plays such a central role in daily oral care.
“How often should I use fluoride toothpaste?”
→ For most people, brushing with fluoride toothpaste twice daily is sufficient.
“What is dental fluorosis?”
→ Fluorosis is a cosmetic change in enamel appearance that can occur if a child ingests too much fluoride while teeth are still developing (usually under the age of 6). Most cases linked to toothpaste are mild and do not affect tooth function or health.⁵
Sources
1. Amaechi, B.T., AbdulAzees, P.A., Alshareif, D.O. et al. Comparative efficacy of a hydroxyapatite and a fluoride toothpaste for prevention and remineralization of dental caries in children. BDJ Open 5, 18 (2019). https://doi.org/10.1038/s41405-019-0026-8
2. American Dental Association. Fluoride. ADA Oral Health Topics. American Dental Association. Available at: https://www.ada.org/resources/research/science-and-research-institute/oral-health-topics/fluoride. Accessed February 4, 2026.
3. Dharmaratne, R. W. (2018). Exploring the role of excess fluoride in chronic kidney disease: A review. Journal of the Royal Society of Medicine Short Reports, 9(11). https://doi.org/10.1177/0960327118814161
4. Iamandii I, De Pasquale L, Giannone ME, Veneri F, Generali L, Consolo U, Birnbaum LS, Castenmiller J, Halldorsson TI, Filippini T, Vinceti M. Does fluoride exposure affect thyroid function? A systematic review and dose-response meta-analysis. Environ Res. 2024 Feb 1;242:117759. doi: 10.1016/j.envres.2023.117759. Epub 2023 Nov 28. PMID: 38029816.
5. Kanduti D, Sterbenk P, Artnik B. FLUORIDE: A REVIEW OF USE AND EFFECTS ON HEALTH. Mater Sociomed. 2016 Apr;28(2):133-7. doi: 10.5455/msm.2016.28.133-137. Epub 2016 Mar 25. PMID: 27147921; PMCID: PMC4851520.
6. Levine, R. What concentration of fluoride toothpaste should dental teams be recommending?. Evid Based Dent 20, 74–75 (2019). https://doi.org/10.1038/s41432-019-0040-7
7. National Institutes of Health, Office of Dietary Supplements. Fluoride: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. Updated April 11, 2025. Available at: https://ods.od.nih.gov/factsheets/Fluoride-HealthProfessional/. Accessed February 4, 2026.
8. O'Hagan-Wong K, Enax J, Meyer F, Ganss B. The use of hydroxyapatite toothpaste to prevent dental caries. Odontology. 2022 Apr;110(2):223-230. doi: 10.1007/s10266-021-00675-4. Epub 2021 Nov 22. PMID: 34807345; PMCID: PMC8930857.
9. Wright JT, Hanson N, Ristic H, Whall CW, Estrich CG, Zentz RR. Fluoride toothpaste efficacy and safety in children younger than 6 years: a systematic review. J Am Dent Assoc. 2014 Feb;145(2):182-9. doi: 10.14219/jada.2013.37. PMID: 24487610.
10. Mazzoleni S, Gargani A, Parcianello RG, Pezzato L, Bertolini R, Zuccon A, Stellini E, Ludovichetti FS. Protection against Dental Erosion and the Remineralization Capacity of Non-Fluoride Toothpaste, Fluoride Toothpaste, and Fluoride Varnish. Applied Sciences. 2023; 13(3):1849. https://doi.org/10.3390/app13031849
