Fluoride treatments are ubiquitous because they have long been thought to be the best cavity prevention. But no long-term studies actually demonstrate the safety of fluoride treatments, particularly in children, and many studies suggest fluoride can be harmful to your overall health.
The American Dental Association (ADA), Centers for Disease Control and Prevention (CDC), and Environmental Protection Agency (EPA) have all touted fluoride’s benefits without long-term safety studies. Now the EPA is losing court battles on fluoride.
We review the potential dangers of fluoride treatments at the dentist and how to prevent cavities in a much safer, whole-body way.
What Is Fluoride?
Fluoride is a naturally-occurring mineral. You can find small amounts of fluoride in groundwater. It’s the most abundant form of fluorine (F on the periodic table). However, the fluoride used in oral hygiene products and dental treatments is not the same as the mineral found in nature.
These compounds are typically the fluoride sources in toothpaste, mouthwashes, fluoridated drinking water, and dental products:
- Sodium fluoride (NaF)
- Stannous fluoride (SnF2)
- Sodium monofluorophosphate (Na₂PO₃F)
- Hexafluorosilicic acid (H2SiF6)
Fun fact: Hexafluorosilicic acid is a phosphate fertilizer byproduct — effectively industrial waste that has been repackaged as vital to public health.
Fluoride treatments administered at a dentist’s office often come in the form of a gel, foam, or varnish. Although conventional dentists use fluoride varnish on children at risk of tooth decay, the high fluoride content may lead to fluorosis, hormone disruption, and lower IQ via swallowing or absorption into the bloodstream. You can tell your dentist to skip this treatment for yourself or your children.
Proponents of fluoride claim that free fluoride ions release once applied to teeth. These fluoride ions help remineralize teeth, interfere with oral bacteria’s production of enamel-eroding acid, and make your teeth more resistant to future decay.
Opponents of fluoride do not always refute the benefits of fluoride but simply add that the long-term and whole-body adverse effects of high-fluoride treatments outweigh the health benefits.
A huge anti-fluoride argument is that developed nations have all seen reductions in dental cavities, whether they fluoridate their public water supplies or not. Check out this chart for more info.
Some anti-fluoride advocates argue that more fluoride is swallowed from toothpaste and dental treatments than experts estimate, leading to the adverse effects discussed below. But other advocates argue that even the low ingestion rate that experts estimate is still too much fluoride.
Danger #1: Dental Fluorosis
Even mainstream healthcare organizations recognize that high fluoride exposure can lead to dental fluorosis. Excessive fluoride consumption, such as during dental treatments on young children, leads to permanent teeth discoloration.
Kids are particularly vulnerable to this mild disorder, characterized by lasting white or brown spots or streaks on the tooth surface.
Dental fluorosis is associated with water fluoride levels in excess of 1.5 ppm (parts per million). Artificially fluoridated water sources aimed for 1.0 ppm for the optimal benefits and minimal downsides until 2015 when the U.S. Health Dept recommended lowering the target to 0.7 ppm.
Related Reading: The Dangers of Composite Fillings
Danger #2: Acute Fluoride Toxicity
If you ingest more fluoride than intended (e.g., your child gets into a full tube of fluoride toothpaste), acute fluoride toxicity may set in. This should not happen under a dentist’s supervision, but high-fluoride dental treatments do have the risk of being swallowed.
Moderate symptoms include:
- Abdominal pain
- Nausea
- Vomiting
- Diarrhea
- Excess salivation
If enough is ingested, severe symptoms may occur:
- Irregular heartbeat
- Muscle spasms
- Seizures
- Coma
- Hypocalcemia (low blood calcium levels)
If you suspect acute fluoride toxicity, don’t wait for symptoms. Call Poison Control immediately at 1-800-222-1222 (U.S.).
Danger #3: Skeletal Fluorosis
Although rare outside India and China, skeletal fluorosis is gaining mainstream recognition as a side effect of fluoride consumption at high doses. It has no treatment besides stopping fluoride ingestion.
The following symptoms and conditions may accompany a skeletal fluorosis diagnosis:
- Dental fluorosis
- Vitamin D deficiency
- Increased risk of fractures
- Reduced bone mass
- Skeletal pain
- Limited mobility
Danger #4: Neurological Issues (Including Lowered IQ)
Fluoride exposure may lead to neurological issues. Even mainstream health experts and researchers have recently begun to admit that fluoride intake at only twice the recommended level can cause major neurological adverse effects, particularly in children.
Fluoride can cross the blood-brain barrier when ingested, disrupting the brain’s normal metabolic processes and increasing oxidative stress in your central nervous system.
A 2021 study concluded, “Chronic exposure may be linked to decreased intelligence, memory deficits, learning difficulties, and ADHD.” These scientists also noted that very little research has been done on adolescent fluoride exposure, including during dental treatments.
In April 2025, HHS Secretary Robert F. Kennedy Jr. said, “The evidence against fluoride is overwhelming. In animal models, and in human models, we know that it causes IQ loss.”
Kennedy seemed to be referring to this National Toxicology Program report that demonstrated IQ loss in children in communities with twice the recommended levels of fluoride in the water (1.5 ppm vs 0.7 ppm). However, this “recommendation” is neither a law nor a regulation, and he did not disparage the use of fluoride treatments in dental care.
Context: In 1984 and again in 2006, the WHO recommended 1.5 ppm for fluoridated water levels. That amount is now widely agreed upon to be dangerous to neurological health.
But fluoride treatments found in dental offices typically have much higher concentrations of fluoride than drinking water or toothpaste. Even a small amount swallowed accidentally, twice a year or more often, should pose a health risk to children.
Danger #5: Hormone Dysfunction
Fluoride consumption may lead to thyroid issues, reproductive issues, and kidney problems. It is widely known that fluoride can disrupt the endocrine system which regulates your hormone levels, but fluoride proponents argue adverse effects are only present at extremely high levels.
Of course, fluoride treatments and fluoride supplements contain high levels of fluoride.
One scientific review found that sodium fluoride (considered the “safer” source of fluoride) negatively impacts your thyroid, parathyroid, pituitary, and adrenal glands, as well as your pancreas’s insulin production.
A more recent systematic review and meta-analysis confirmed fluoridated drinking water’s harmful effects on thyroid function in children, suggesting high fluoride intake is associated with hypothyroidism and goiters in both children and adults.
Danger #6: Increased Risk of Certain Cancers
Fluoride may be linked to certain cancers.
Fluoride treatments seem to pose little risk of cancer due to the infrequency of professional dental fluoride treatments, except when combined with other sources of fluoride exposure or repeated fluoride varnish treatments.
A primary method of fluoridating drinking water is adding the industrial waste product, hexafluorosilicic acid, to a community’s water system. Hexafluorosilicic acid contains trace amounts of arsenic (a carcinogen) and can also leach lead (a carcinogen) from pipes as it goes to your faucet, delivering a one-two punch of raising cancer risk.
Fluoride has been connected with increasing the risk of developing the following cancers:
- Oral cancer
- Pharynx cancer
- Colorectal cancer
- Liver or gallbladder cancer
- Bladder cancer
- Brain tumors
- Multiple myeloma
- Hodgkin’s lymphoma
- Non-Hodgkin lymphoma
- Lung cancer
- Osteosarcoma, particularly in males
How can I find out how much fluoride is in my tap water?
You can find out your community’s water fluoridation level by either checking the CDC’s “My Water’s Fluoride” website or checking with your local utility.
In general, 0.7 ppm or less is far better than 1.0+ ppm. My hope is to see that number drop to 0.0 ppm of added fluoride in water supply.
How to Safely Prevent Cavities
You can fight and prevent tooth decay with these safe, natural treatments for better dental health:
- Empower your oral microbiome. Your mouth is naturally equipped to remineralize teeth after demineralization occurs. Feed your mouth healthful food, and the billions of beneficial bacteria in your oral cavity should help fight and prevent dental caries.
- Avoid sugar and starchy carbs. The harmful bacteria that can live on your teeth feed on sugars and carbohydrates, secreting acids that wear away at your tooth enamel. Starve the bad bacteria and opt for protein, fats, and plenty of water.
- Brush and floss regularly. A soft-bristled toothbrush can disrupt the bad bacteria that builds up on your tooth surface. Flossing addresses the interdental plaque that your toothbrush can’t reach. Disrupting then spitting out the bad bacteria helps prevent cavities.
- Use a microbiome-friendly toothpaste. Hydroxyapatite has gained recent popularity as a fluoride alternative, but nanoparticles of hydroxyapatite have been found in people’s lungs and all over where it may disrupt bodily processes. Avoid charcoal toothpastes, too. Stick to a prebiotic toothpaste like Revitin which strengthens your oral microbiome to naturally remineralize your teeth.
- Don’t forget your twice yearly checkups. It might be a cliche, but you need to see your dentist twice a year for a (hopefully fluoride-free) cleaning and disease prevention checkup. Dentists can spot oral diseases, including cavities, before they’re a permanent problem.
Read More: How to Prevent Tooth Decay Naturally (11 Steps)
Here’s How a Good Dentist Can Keep Your Teeth Healthy (No Fluoride Needed)
Holistic and biological dentists use natural methods to empower your oral microbiome to do what it is designed to do — keep your mouth healthy. A strong microbiome helps remineralize teeth, so a good dentist should not use fluoride treatments, mercury amalgam fillings, or (except in the most extreme cases) antibacterials.
Instead, your dentist can utilize non-toxic, biocompatible materials and methods to treat oral health problems. Here at Rejuvenation Dentistry, we consult on diet and lifestyle because we believe your oral health impacts your whole body health and vice-versa.
Schedule your appointment with Rejuvenation Dentistry today and start living your new life with a gleaming, all-natural smile!
Sources
- Niazi, F. C., & Pepper, T. (2022). Dental fluorosis. Full text: https://www.ncbi.nlm.nih.gov/books/NBK585039/
- Joseph, A., Rajan, R., Paul, J., Cherian, K. E., Kapoor, N., Jebasingh, F., ... & Paul, T. V. (2022). The continuing crippling challenge of skeletal fluorosis–Case series and review of literature. Journal of Clinical and Translational Endocrinology: Case Reports, 24, 100114. Full text: https://www.sciencedirect.com/science/article/pii/S2214624522000089
- Taylor, K. W., Eftim, S. E., Sibrizzi, C. A., Blain, R. B., Magnuson, K., Hartman, P. A., ... & Bucher, J. R. (2025). Fluoride exposure and children’s IQ scores: a systematic review and meta-analysis. JAMA pediatrics. Full text: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2828425
- Żwierełło, W., Maruszewska, A., Skórka-Majewicz, M., & Gutowska, I. (2023). Fluoride in the central nervous system and its potential influence on the development and invasiveness of brain tumours—a research hypothesis. International Journal of Molecular Sciences, 24(2), 1558. Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC9866357/
- Adkins, E. A., & Brunst, K. J. (2021). Impacts of fluoride neurotoxicity and mitochondrial dysfunction on cognition and mental health: a literature review. International journal of environmental research and public health, 18(24), 12884. Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC8700808/
- Skórka-Majewicz, M., Goschorska, M., Żwierełło, W., Baranowska-Bosiacka, I., Styburski, D., Kapczuk, P., & Gutowska, I. (2020). Effect of fluoride on endocrine tissues and their secretory functions--review. Chemosphere, 260, 127565. Abstract: https://pubmed.ncbi.nlm.nih.gov/32758781/
- Iamandii, I., De Pasquale, L., Giannone, M. E., Veneri, F., Generali, L., Consolo, U., ... & Vinceti, M. (2024). Does fluoride exposure affect thyroid function? A systematic review and dose-response meta-analysis. Environmental Research, 242, 117759. Abstract: https://pubmed.ncbi.nlm.nih.gov/38029816/
- Takahashi, K., Akiniwa, K., & Narita, K. (2001). Regression analysis of cancer incidence rates and water fluoride in the USA based on IACR/IARC (WHO) data (1978-1992). Journal of Epidemiology, 11(4), 170-179. Full text: https://www.jstage.jst.go.jp/article/jea1991/11/4/11_4_170/_pdf
- Grandjean, P., & Olsen, J. H. (2004). Extended follow-up of cancer incidence in fluoride-exposed workers. Journal of the National Cancer Institute, 96(10), 802-803. Full text: https://academic.oup.com/jnci/article-abstract/96/10/802/2905308
- Kharb, S., Sandhu, R., & Kundu, Z. S. (2012). Fluoride levels and osteosarcoma. South Asian Journal of Cancer, 1(2), 76. Full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC3876610/
