Fluorine

Fluorine / Fluoride: A Comprehensive Encyclopedic Reference

1. Identity, Chemical Nature, and Common Names

Fluoride is the ionic form of fluorine, a halogen and the most electronegative of the elements of the periodic table. In nutritional and supplement contexts, the two terms are closely linked but distinct: fluorine refers to the elemental form (atomic number 9; chemical symbol F), while fluoride denotes the negatively charged ion (F⁻) that exists in foods, water, the human body, and most supplemental preparations. Fluorides are salts of the chemical element fluorine.

Fluoride is the ionic form of the naturally occurring fluorine element. The anion increases the structural stability of teeth and bones through interactions with calcium phosphates.

Common chemical forms used in supplements and dental products include:

• Sodium fluoride (NaF) — the most widely used form in dietary supplements, fluoridated water, and pharmaceutical preparations.
• Sodium monofluorophosphate (Na₂PO₃F) — commonly used in fluoride toothpastes and some oral supplements.
• Stannous fluoride (SnF₂) — used in some prescription dental gels and toothpastes.
• Acidulated phosphate fluoride (APF) — used in professional dental applications.

Only a few dietary supplements contain fluoride, usually in the form of sodium fluoride. Most of these products are multivitamin/multimineral supplements, multivitamins plus fluoride, or supplements containing trace minerals only. Some fluoride supplements, usually intended for children, are in the form of drops.

2. Natural Sources and Food Forms

Fluoride, a mineral, is naturally present in many foods and available as a dietary supplement. Soil, water, plants, and foods contain trace amounts of fluoride. Most of the fluoride that people consume comes from fluoridated water, foods and beverages prepared with fluoridated water, and toothpaste and other dental products containing fluoride.

Dietary sources of fluoride include naturally fluoridated water as well as dietary fluoride supplements (including artificially fluoridated water, milk, and salt) and other foods and drinks prepared with fluoridated water.

Key dietary sources include:

• Tea: In countries where tea is largely consumed, it is a significant source of fluoride. Fluoride concentrations in tea leaves range from 26 to 820 mg/kg, and in tea infusions from 0.29 to 8.85 mg/L.
• Seafood and fish with bones: Generally, raw fruits and vegetables, meat, and unprocessed foods and beverages contain low concentrations of fluoride. However, concentrations of fluoride in mechanically deboned meat as well as seafoods such as fish and shellfish products containing bone and skin could be greater than 10 mg/kg.
• Fruits and vegetables: The main dietary sources of fluorine are seafood (e.g., oysters, mussels, clams, scallops, octopus, squid), seaweed, fish with bones, and tea. Some fruits (e.g., raisins, oranges) and vegetables (e.g., potatoes, beets), as well as wine, also contain fluorine.
• Brewed tea: Brewed tea typically contains higher levels of fluoride than most foods, depending on the type of tea and its source, because tea plants take up fluoride from soil.

According to the EPA, typical daily fluoride intakes in the United States from foods and beverages (including fluoridated drinking water) are 1.2 to 1.6 mg for infants and toddlers younger than 4 years, 2.0 to 2.2 mg for children age 4–11 years, 2.4 mg for those age 11–14 years, and 2.9 mg for adults.

3. Historical and Traditional Use

Unlike many botanical supplements with centuries of deliberate human use, fluoride's history in health practice is primarily a 20th-century scientific and public health story rooted in epidemiological observation rather than traditional herbalism or folk medicine. Nevertheless, the progression from observation to application is notable and well-documented.

Early Observations (Early 20th Century)

The first documentation of fluoride's effects began with three independent reports from Italy, America, and the U.K. in the early 1900s noting that individuals with mottled, brown-stained teeth had lower incidences of dental caries.

Black and McKay first recognised the preventive effect of fluoride in Colorado Springs at the beginning of the 20th century. In 1931, Churchill identified a higher concentration of fluoride in Colorado Springs' water.

Dr. H. Trendley Dean renamed "Colorado brown stain" the more scientific "fluorosis" and did a several-year survey to figure out just how much fluorosis there was in the US. What he found was that in 26 states, kids with fluorosis also had fewer "dental caries" — a catch-all term for tooth decay.

Water Fluoridation as a Public Health Measure (1945 Onward)

In 1945, Grand Rapids became the first city in the world to fluoridate its drinking water. During the 15-year project, researchers monitored the rate of tooth decay among Grand Rapids' almost 30,000 schoolchildren. After just 11 years, Dean concluded that the caries rate among Grand Rapids children born after fluoride was added to the water supply dropped more than 60%.

The prevention of caries with fluorides has been proven to be an effective public health measure, and it is considered to be one of the ten greatest achievements of public health in the 20th century.

The history of water fluoridation is a classic example of clinical observation leading to epidemiologic investigation and community-based public health intervention.

Beyond water fluoridation, systemic fluoride had been widely recommended until the 1970s, when the new concept of understanding caries and fluoride's anticariogenic action was introduced. This shifted emphasis toward the topical (post-eruptive) mechanisms of fluoride action, leading to broad adoption of fluoridated toothpastes and professional dental applications globally.

Fluoride also has the unique ability to stimulate new bone formation, and as such, it has been used as an experimental drug for the treatment of osteoporosis.

4. Key Constituents and Mechanisms of Action

Chemical Behavior and Absorption

Fluoride combines reversibly with hydrogen to form the acid, hydrogen fluoride (HF). Much of the physiological behavior of fluoride — for example, its absorption from the stomach, distribution between extra- and intracellular fluid compartments and renal clearance — is due to the diffusion of HF.

After ingestion, fluoride is absorbed by passive diffusion from the gastrointestinal tract, with stomach and upper small intestine absorption accounting for 20–25% and 70–75% of total fluoride absorption, respectively. Plasma fluoride concentrations increase sharply and reach a peak within 20–60 min after ingestion.

Approximately 80% or more of orally ingested fluoride is absorbed in the gastrointestinal tract. In adults, about 50% of absorbed fluoride is retained in the body, with all but 1% stored in bones and teeth. The other 50% is excreted in urine.

Almost 99% of body fluoride is incorporated into the apatite lattice of bones and teeth. The removal of fluoride occurs almost exclusively from the kidneys. In healthy adults, approximately 35% of absorbed fluoride is retained in the body, and in children this is almost 55%.

Mechanism of Action in Dental Caries Prevention

The beneficial effect of fluoride arises primarily from the constant presence of low concentrations of fluoride in the fluid phases of the oral environment.

Fluoride acts by two principal mechanisms against caries:

1. Inhibition of demineralization: Fluoride present in low, sustained concentrations (sub-ppm range) in the oral fluids during an acidic challenge is able to adsorb to the surface of the apatite crystals, inhibiting demineralization.

2. Enhancement of remineralization through fluorapatite formation: Systemically ingested fluoride can change hydroxyapatite into fluorapatite, thus making the teeth more resistant to caries. Fluorapatite Ca₁₀(PO₄)₆F₂ is an enamel mineral much more resistant to acid dissolution than other tooth minerals (carbonated apatite and hydroxyapatite). Fluorapatite results from replacing the OH ion in hydroxyapatite with a fluoride ion.

Fluoride enhances tooth remineralization by accelerating the growth of fluorapatite crystals on the partially demineralized subsurface crystals in the carious lesion.

Fluoride has several other effects, including preventing glycolysis (by acidifying the cytoplasm of cells and inhibiting the enolase enzyme) and preventing tooth decay. Extracellular polysaccharide synthesis is decreased.

Mechanism of Action in Bone

Owing to its high affinity for calcium, fluoride is mainly associated with calcified tissues. The uptake of fluoride into bone results in the conversion of the bone mineral hydroxyapatite into fluorapatite, which alters the general bone lattice and reduces its overall strength at high doses.

Fluoride has the greatest potential as a therapy for osteoporosis once bone has been lost. It has been demonstrated both experimentally and clinically to stimulate bone formation directly and to increase bone mass in patients who already have osteoporosis.

Essential Nutrient Status

Although fluoride is not considered an essential nutrient, it has a valuable role in improving oral health. Fluoride has been viewed as the fundamental element for prevention of dental caries.

5. Scientific Evidence by Area of Use

5.1 Dental Caries Prevention

Evidence strength: Strong (well-established for topical use; moderate for water fluoridation in contemporary studies)

Fluoride inhibits or reverses the initiation and progression of dental caries (tooth decay) and stimulates new bone formation.

Early epidemiological studies: The prevalence of dental caries in children living in communities with fluoridated water was 50–70% lower than in children living in areas without fluoridated water in studies conducted prior to the late 1980s.

Cross-sectional NHANES study (2018): The authors analyzed data on 7,000 children age 2 to 8 years and 12,604 children and adolescents age 6 to 17 years who participated in NHANES from 1999 to 2004 and 2011 to 2014. The results showed that living in a county in which 75% or more of the drinking water contained at least 0.7 mg/L fluoride was associated with a 30% reduction in the rate of caries in primary teeth and a 12% reduction in the rate of caries in permanent teeth.

Cochrane Review (updated 2024): Contemporary studies indicate that initiation of community water fluoridation may lead to a slightly greater reduction in decayed, missing, or filled primary teeth (dmft) and may lead to a slightly greater increase in the proportion of caries-free children, but with smaller effect sizes than earlier studies. This evidence was of low certainty. There is insufficient evidence to determine the effect of cessation of community water fluoridation on caries.

The original 2015 Cochrane Review noted that the initiation of water fluoridation results in reductions in caries which translate into a 35% reduction in primary teeth and a 26% reduction in permanent teeth, with an increase of 15% in the percentage of children free of decay experience in primary teeth and an increase of 14% in the percentage of children free of decay experience in permanent teeth. However, there is very little contemporary evidence, meeting the review's inclusion criteria, that has evaluated the effectiveness of water fluoridation for the prevention of caries. Over 97% of the studies were at high risk of bias and there was substantial between-study variation.

Fluoride supplements in children: Children who take dietary supplements that contain fluoride have a lower risk of tooth decay and tooth loss. Many dentists recommend fluoride supplements for children living in areas where the water supply is not fluoridated or contains too little natural fluoride. We don't know how fluoride supplements affect adults.

The use of fluoridated dental products and adequate intakes of fluoride reduce the occurrence of caries throughout life by promoting tooth mineralization and re-mineralization.

5.2 Bone Health and Osteoporosis

Evidence strength: Mixed to negative for fracture reduction; bone density increases observed but functional outcomes inconsistent

Interest in fluoride's effect on bone density stems back to the mid-twentieth century, when scientists first started using fluoride as a drug to build bone mass in patients with osteoporosis. From the 1960s to the 1990s, numerous clinical trials examined the effect of high daily doses of fluoride (20–34 mg/day) on bone density and fracture rates. The results were not what fluoride advocates had anticipated: although fluoride did increase spinal and pelvic bone mass, it did little to reduce fracture rates in these bones.

New England Journal of Medicine RCT (Riggs et al., 1990): To assess the effect of fluoride treatment on the fracture rate in osteoporosis, a four-year prospective clinical trial was conducted in 202 postmenopausal women with osteoporosis and vertebral fractures randomly assigned to receive sodium fluoride (75 mg per day) or placebo. All received a calcium supplement (1500 mg per day). As compared with the placebo group, the treatment group had increases in median bone mineral density of 35% (P<0.0001) in the lumbar spine, 12% (P<0.0001) in the femoral neck, and 10% (P<0.0001) in the femoral trochanter, but the bone mineral density decreased by 4% (P<0.02) in the shaft of the radius (predominantly cortical bone). Despite substantial increases in trabecular bone density, fracture rate reductions were not demonstrated, illustrating the dissociation between bone density and bone quality at high doses.

Meta-analysis of RCTs: Spine BMD increased by 7.9% (95% CI: 5.4%, 10.5%, p<0.001, n=1,774) and hip BMD by 2.1% (95% CI: 0.9%, 3.4%, p<0.01, n=1,434) after treatment with fluoride, but with evidence of significant heterogeneity.

Rather than prevent bone fractures in osteoporosis patients, fluoride therapy (at doses of 20–34 mg/day) was repeatedly found to increase fracture rates. Based on this track record, the Food & Drug Administration has rejected fluoride therapy as an approved way of treating osteoporosis.

Slow-release formulations: A positive clinical effect was shown when fluoride (23 mg/day) is administered in a sustained-release form. Research on slow-release sodium fluoride showed improved trabecular connectivity and bone quality compared to immediate-release formulations, suggesting that dose and formulation are critical variables.

Bone fractures from fluoridated water: Research has shown mixed results, from a positive association, to no association, to even a protective effect of fluoride. A meta-analysis looking at 13 cohort studies did not find an association of exposure to fluoride from drinking water (ranging from 7 to 44 years) and an increased risk of hip fractures in older adults. The authors noted potential confounding factors, such as increased calcium supplement use in this age group, which can decrease fluoride absorption. A cohort study published in 2021 looking at the association of fractures in postmenopausal women and fluoride as measured in urine and dietary intakes found higher rates of hip fractures when comparing the highest to lowest intakes of fluoride and urinary fluoride. The mean dietary intake was about 2 mg daily that included drinking water fluoridated at about 1 mg per liter.

5.3 Neurodevelopment and Cognition

Evidence strength: Emerging, moderate confidence at high exposure levels; actively contested; limited data at low/recommended exposure levels

A 2006 evaluation by the National Research Council (NRC) found support for an association between consumption of high levels of naturally occurring fluoride in drinking water and adverse neurological effects in humans and recommended further investigation. The evidence reviewed at that time was from dental and skeletal fluorosis-endemic regions of China.

The 2024 National Toxicology Program Monograph concluded — with moderate confidence — that higher fluoride exposure is associated with lower IQ in children. The human data provided the strongest evidence, and because most of the high-quality epidemiological studies focused on IQ in children, they formed the primary basis for the conclusions.

By the end of 2024, the number of epidemiological studies examining this association had increased to include over 70 studies conducted across 12 countries, utilizing diverse study designs, and 22 high-quality studies. In January 2025, NTP authors published a detailed meta-analysis of 74 epidemiological studies in JAMA Pediatrics, reporting an inverse association between fluoride exposure and children's IQ scores.

The review found, with moderate confidence, that higher estimated fluoride exposures — as in approximations of exposure such as drinking water fluoride concentrations that exceed the World Health Organization guidelines for drinking-water quality of 1.5 mg/L of fluoride — are consistently associated with lower IQ in children.

The body of evidence from studies in adults is also limited and provides low confidence that fluoride exposure is associated with adverse effects on adult cognition.

The U.S. National Toxicology Program concluded, in their assessment finalized in 2024, that fluoride exposure corresponding to water concentrations of ≥ 1.5 mg/L were associated with adverse neurodevelopmental outcomes in children. Health Canada concluded in their 2023 assessment that "there is not a sufficient basis at this time to recommend a specific point of departure and health-based value for neurocognitive effects."

5.4 Kidney Health

There remains a question of potential health risks with specific conditions, such as kidney disease, in which people may not be able to excrete excess fluoride if exposed, increasing the risk of toxicity. There is also a risk of fluoride causing chronic kidney disease (CKD), as shown in studies of people exposed to excessive fluoride due to unusually high levels in the groundwater who develop CKD.

6. Body Systems and Health Areas Associated with Fluoride

• Oral/Dental System: The best-established area of use. The daily intake recommendations for fluoride are based on the safest and most effective intakes to prevent dental caries. The use of fluoridated dental products and adequate intakes of fluoride reduce the occurrence of caries throughout life by promoting tooth mineralization and re-mineralization.
• Skeletal System: Owing to its high affinity for calcium, fluoride is mainly associated with calcified tissues. Its ability to inhibit, and even reverse, the initiation and progression of dental caries is well known. It also has the unique ability to stimulate new bone formation.
• Renal System: The removal of fluoride occurs almost exclusively from the kidneys. Impaired renal function can therefore lead to fluoride accumulation and toxicity.
• Neurological System: An area of active investigation. The NTP 2024 monograph and associated JAMA Pediatrics (2025) meta-analysis found moderate-confidence evidence of an inverse association between high fluoride exposure and IQ in children, though the relationship at levels used in U.S. water fluoridation (0.7 mg/L) remains under regulatory review.

7. Dosage Forms, Intake Recommendations, and Supplemental Dosages

Adequate Intakes (AIs) Established by the Food and Nutrition Board (FNB)

The FNB found the data insufficient to derive Estimated Average Requirements (EARs) for fluoride. Therefore, the board established AIs for all ages using estimated intakes shown to maximize reductions in the incidence of dental caries without unwanted side effects, such as dental fluorosis, a chronic condition resulting from the consumption of too much fluoride when teeth are developing.

The suggested AI for infants from birth to 6 months is 0.01 mg/day, whereas for children older than 6 months and adults the AI is estimated as 0.05 mg/kg body weight.

Adequate intakes for adults 19+ years have been established at 4 mg a day for men and 3 mg for women. For women who are pregnant or lactating, the AI is 3 mg.

Tolerable Upper Intake Levels (ULs)

The Tolerable Upper Intake Level (UL) for fluoride for all adults 19+ years of age and pregnant and lactating women is 10 mg daily; a UL is the maximum daily intake unlikely to cause harmful effects on health.

Tolerable upper intake levels (UL) of 1.0, 1.6, and 2.0 mg/day were established for infants, toddlers, and children 4–8 years, respectively. For children and adults aged 9–14 and ≥15 years, ULs of 5 and 7 mg/day were established, respectively, based on increased risk for bone fractures observed in randomised controlled trials among postmenopausal women.

EFSA additionally notes that these ULs are considered protective against other possible adverse effects of fluoride, including neurodevelopmental outcomes.

Water Fluoridation Standards

The US Public Health Service's current recommended amount of fluoride in a community water system is 0.7 mg/L and the EPA requires public water systems to keep the concentration of fluoride below 4.0 mg/L. The World Health Organization recommends that drinking water should have no more than 1.5 mg/L of fluoride.

Pediatric Supplemental Dosages (ADA Schedule)

For children aged 6–16 years: if water fluoride is <0.3 ppm, 1.0 mg/day is given; if water is 0.3–0.6 ppm, 0.50 mg/day is given. No supplement is needed if water fluoride ≥0.6 ppm.

Dosages Used in Osteoporosis Clinical Trials

Clinical trials investigating fluoride for osteoporosis treatment have used doses significantly higher than nutritional intakes. A four-year prospective RCT used sodium fluoride at 75 mg per day in 202 postmenopausal women. Another clinical assessment involved treatment with fluoride 30 ± 8 mg/day (equivalent to 66 ± 17 mg NaF/day) and calcium 1500 mg/day for 28 ± 18 months. These doses are pharmacological, far above nutritional Adequate Intakes, and are not approved for clinical use.

Supplement Forms Available

A few dietary supplements, including some multivitamin/mineral products, contain fluoride. Liquid fluoride drops for children are also available.

8. Safety Considerations

Dental Fluorosis

Dental fluorosis occurs as a result of excess fluoride ingestion during tooth formation. Enamel fluorosis and primary dentin fluorosis can only occur when teeth are forming, and therefore fluoride exposure (as it relates to dental fluorosis) occurs during childhood. In the permanent dentition, this would begin with the lower incisors, which complete mineralization at approximately 2–3 years of age, and end after mineralization of the third molars.

The white opaque appearance of fluorosed enamel is caused by a hypomineralized enamel subsurface; with more severe dental fluorosis, pitting and a loss of the enamel surface occurs, leading to secondary staining (appearing as a brown color).

With regard to dental fluorosis, at a fluoride level of 0.7 ppm, the percentage of participants with fluorosis of aesthetic concern was approximately 12% (95% CI 8% to 17%; 40 studies, 59,630 participants).

Skeletal Fluorosis

Getting too much fluoride over a long period of time can lead to a condition called skeletal fluorosis. This very rare condition causes joint pain and stiffness, weak bones, muscle loss, and nerve problems. It is not caused by standard amounts of fluoride in public tap water.

The uptake of fluoride into bone results in the conversion of the bone mineral hydroxyapatite into fluorapatite, which alters the general bone lattice and reduces its overall strength. Vertebrates exposed to high fluoride have mechanically weaker bones. This increased brittleness is associated with skeletal dysmorphia and higher risk of fracture.

When constantly consumed in large amounts for a long time, fluoride can cause chronic disease. The first sign of chronic toxicity is observed through changes in the dental organs, which show a creamy-white surface, white and yellow spots, lines or striations, and porosity. In more severe injuries, the tooth enamel becomes weak, brittle, prone to fractures or ruptures, and has significant areas of wear and tear.

Acute Toxicity

Swallowing extremely large amounts of fluoride from dental products or dietary supplements can cause nausea, vomiting, abdominal pain, diarrhea, bone pain, and even death in rare cases.

Kidney Disease and Fluoride Accumulation

Toxicity not only depends on the intake but is also related to the exposure time, diet, and nutritional status of the individual, as well as the altitude of the location. Because fluoride is primarily renally cleared, individuals with kidney disease face a heightened risk of accumulation and toxic effects.

Drug Interactions

Fluoride has no known, clinically relevant interactions with medications in general at normal dietary intake levels. However, a specific pharmaceutical interaction is documented:

Fluoride is a constituent of voriconazole (an oral antifungal medication), and long-term use (e.g., for 4 months or more) of this medication can lead to high fluoride concentrations in serum and plasma. The prescribing information for voriconazole advises discontinuation of voriconazole if skeletal fluorosis or periostitis (inflammation of the membrane surrounding and protecting the bones) develops.

Fluoride is not known to interact or interfere with any medicines or dietary supplements at standard nutritional intake levels, according to NIH ODS.

Bioavailability Modifiers

Nutrition is also important for controlling the serum level of fluoride, as ions such as calcium, magnesium, and aluminum can reduce the bioavailability of fluoride. This means that dietary calcium and magnesium intakes, as well as the use of antacids containing aluminum or magnesium, may modulate fluoride absorption.

Neurotoxicity at High Exposures

A 2024 NTP systematic review found, with moderate confidence, that higher estimated fluoride exposures — at drinking water fluoride concentrations that exceed the World Health Organization guideline of 1.5 mg/L — are consistently associated with lower IQ in children. The evidence base for neurotoxicity at fluoride concentrations used in U.S. water fluoridation (0.7 mg/L) remains under active regulatory review.

Infant Formula Caution

Infants fed formula reconstituted with fluoridated water may receive as much as 1.0 mg/day. Some evidence shows that the prevalence of mild enamel fluorosis in the primary teeth, but not the permanent teeth, is higher among formula-fed infants than infants fed cow's milk, which has a low fluoride concentration similar to that of human milk.

Assessment of Fluoride Status

Individual fluoride status is not typically assessed, although fluoride concentrations can be measured in plasma, saliva, urine, bones, nails, hair, and teeth. Criteria for adequate, high, or low levels of fluoride in the body have not been established.

References

• NIH Office of Dietary Supplements — Fluoride: Health Professional Fact Sheet
• NIH Office of Dietary Supplements — Fluoride: Consumer Fact Sheet
• Fluoride — PMC / NIH (Dietary Sources, Metabolism, and Oral Health)
• Dietary Reference Intakes for Fluoride — NCBI Bookshelf (National Academies, 1997)
• Fluoride — Linus Pauling Institute, Oregon State University
• Fluoride — The Nutrition Source, Harvard T.H. Chan School of Public Health
• The History of Public Health Use of Fluorides in Caries Prevention — PMC
• The Untold Story of Fluoridation: Revisiting the Changing Perspectives — PMC
• The Story of Fluoridation — National Institute of Dental and Craniofacial Research (NIDCR)
• Achievements in Public Health, 1900-1999: Fluoridation of Drinking Water — CDC MMWR
• Water Fluoridation for the Prevention of Dental Caries — Cochrane Library (Updated 2024)
• Water Fluoridation for the Prevention of Dental Caries — Cochrane Library (2015)
• Fluoride and Dental Caries — Toxicological Profile for Fluorides — NCBI Bookshelf
• Mechanisms of Action of Fluoride for Caries Control — PubMed
• Fluoride Varnishes for Preventing Occlusal Dental Caries: A Review — PMC
• The Role of Fluoride on Caries Prevention — StatPearls / NCBI Bookshelf
• Role of Fluoride in Dentistry: A Narrative Review — PMC
• Effect of Fluoride Treatment on the Fracture Rate in Postmenopausal Women with Osteoporosis — New England Journal of Medicine (Riggs et al., 1990)
• Effects of Treatment with Fluoride on Bone Mineral Density and Fracture Risk: A Meta-Analysis — NCBI (DARE)
• The Role of Fluoride in the Prevention of Osteoporosis — PubMed
• Chronic Fluoride Toxicity: Dental Fluorosis — PMC
• Principles of Fluoride Toxicity and the Cellular Response: A Review — PMC
• Fluoride in Drinking Water and Skeletal Fluorosis: A Review of the Global Impact — PubMed
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• Fluoride Exposure: Neurodevelopment and Cognition — National Toxicology Program (NTP), NIEHS
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• Addressing Critiques of the Evidence Linking Fluoride and Children's IQ — PMC (Annals of Global Health, 2025)
• Considerations on Optimal Fluoride Intake using Dental Fluorosis and Dental Caries Outcomes — A Longitudinal Study (Iowa Fluoride Study) — PMC
• Patterns of Fluoride Intake from 6 to 17 Years of Age: The Iowa Fluoride Study — PMC
• Updated Consumer Risk Assessment of Fluoride in Food and Drinking Water (EFSA-related) — PMC
• Fluoride in Diet — MedlinePlus Medical Encyclopedia
• Fluoride Supplements: A Brief Overview — American Dental Association
• Fluoride in Dental Caries Prevention and Treatment: Mechanisms, Clinical Evidence, and Public Health Perspectives — Healthcare (MDPI), 2025