Water fluoridation: Can we refocus our efforts to help our communities win the battle against dental caries?

Systemic water fluoridation has a long and intricate history from the first community fluoridation program in 1945 in Grand Rapids, Michigan, to today with its heightening controversy.¹ While fluoride has been shown to effectively reduce dental caries, it has also sparked debate over potential health risks, dividing the dental community and prompting public fear.¹ With fluoridated water available to almost 70% of the US population, lawmakers in states like Florida, Utah, Nebraska, Arkansas, Tennessee, Kentucky, and Georgia have recently introduced bills to end mandates that require fluoride in the public water supply or to possibly ban water fluoridation altogether.^1,2 This may be only the beginning with the possibility of other states set to follow suit.

Is water fluoridation going to be a wedge that will divide communities, health-care professionals, and the patient-provider relationship? I believe it is important to address some key questions surrounding water fluoridation and the fluoride controversy. This can help us explore evidence and evaluate the potential benefits and risks, thus providing beneficial recommendations and treatments that prioritize the well-being of each individual patient.

Has water fluoridation stopped decay?

Back in 1945, the hope was that water fluoridation would reduce the prevalence of cavities by as much as 50%.² While the benefits of water fluoridation, as a major public health success, are widely acknowledged by organizations such as the Centers for Disease Control and the American Dental Association, disparities still persist.^2,3 There are certain populations that continue to experience high rates of dental decay, highlighting the need for continued preventive efforts and public health programs.⁴ Dental decay remains a significant global health issue, with around 90% of the population affected by it at some point in their lives.^5,6 The challenge is far from over, especially as the ADA reports an increase in postpandemic cases of dental caries even with our current water fluoridation practices.

Most of my family members grew up in Colorado, Idaho, and Utah, where we had fluoridated water. Unfortunately, dental decay has been an issue with almost all my family members, some a lot more than others. It is critical to consider the numerous factors that contribute to an individual's risk for dental decay, and systemic fluoridation is just a small piece in it. Identifying the underlying causes of decay in each patient will help us offer the best possible support for better oral health outcomes.

What is systemic fluoride, and who benefits from it?

Fluoride is freely found in nature primarily in water and air, but it can also be found in certain fruits, vegetables, and teas.² However, water is the primary dietary source of fluoride found both naturally and in many community water supplies where it is added.² The dietary fluoride we intake is quickly absorbed, with about 99% of total body fluoride being stored in the bones and teeth.² The ADA states, “Before teeth break through the gums (erupt), the fluoride taken in from foods, beverages, and dietary supplements strengthens tooth enamel, making it more resistant to decay. This provides a ‘systemic’ benefit.”³

The optimal time of systemic fluoride benefit is mainly from infancy to around 16 years old, when teeth are still developing and before eruption. This age group represents about 20% of the US population and unfortunately continues to have significant struggles with dental decay. Could we better focus our efforts and money on targeting this specific group in regard to systemic fluoride instead of the remaining general population that gets minimal benefit from it?

There are alternative forms of systemic fluoridation other than just community water, such as drops, tablets, vitamins, and prefluoridated water sold in stores.³ Fluoridated milk (not available in the US) is used in other parts of the world and could be a viable alternative source to community water fluoridation in the future.^2,7 Looking into these alternatives and their dosages could be critical as health-care professionals aim to individualize patient care to fit the needs of each patient.

What about fluoride for post-erupted teeth?

Most humans, by age two, will have erupted teeth present in their mouth for their whole life. The ADA states, “After teeth erupt, fluoride helps rebuild (remineralize) weakened tooth enamel and reverses early signs of tooth decay. When you brush your teeth with fluoride toothpaste or use other fluoride dental products, the fluoride is applied to the surface of your teeth. This provides what is called a ‘topical’ benefit.”³

Once tooth development is complete, using topical fluoride—whether from fluoridated water or other origins—does not pose a risk of fluorosis or damage to the tooth structures from excessive fluoride. At this stage, the benefits of fluoride are primarily topical rather than systemic.²

Studies show that fluoride’s primary effect occurs after tooth eruption, making topical fluoride a valuable therapeutic in reducing tooth decay for both children and adults.² A study conducted in October 2024 found that water fluoridation may have been more beneficial before the widespread use of topical fluoride products, such as toothpaste and rinses.⁵ Therefore, for erupted teeth, it appears more effective to deliver fluoride directly through fluoridated dental products rather than relying solely on ingestion.²

Due to the higher concentration of fluoride in some topical fluoride products, it is important to make sure that patients are using these products as directed and not swallowing them. Monitoring or altering the use of topical fluoride products in small children, patients with special needs, elderly, or anyone in cognitive decline is critical to the safety of the individual.

Who is drinking unfiltered tap water?

I’ve been conducting my own research on who is drinking water straight from the tap. I’ve asked mostly dental professionals, many of whom are strong supporters of water fluoridation, whether they actually drink tap water. The results are strikingly similar to a 2022 study of US adults where about one-quarter (or less in my case with dental professionals) drink tap water, while the remaining three-quarters opt for filtered, bottled, or alternative beverages.^8,9

Have you been to a hotel, gym, school, airport, and even a dental office lately? These places all routinely filter water for patrons or provide bottled water (which I am not a fan of). In a survey taken on who is filtering their tap water, more than 90% of American households were and feel it is needed.⁸ It is important to note that some filtration systems do not remove any or all fluoride, but more systems are moving toward broad-based filtration that includes fluoride, lead, BPAs, and other heavy metals. We might not be getting the benefit from water fluoridation like we did before the 1990s when water filtration and bottled waters were not routinely available.

Interestingly, 97% of developed countries like Japan and most of Europe do not consume fluoridated water.² There is also the concern that once water is fluoridated, it becomes challenging to control excessive fluoride intake, as individuals consume varying amounts of water and other fluoride-containing products.²

What about the lower-income at-risk population?

There is a concern that low-income communities will be the most adversely affected by eliminating water fluoridation. Studies show that these groups, particularly children who benefit from systemic fluoride, are less likely to drink tap water or even water in general.^6,10 This could partially be due to the availability of alternative beverages, such as juices, soda, energy drinks, and bottled water, which can be purchased using federal assistance funds.^11,¹²

More importantly, many Americans, especially in these communities, feel their water is unsafe to drink.¹³ For example, some have legitimate concerns about contaminants such as heavy metals, PFAs, pesticides due to environmental factors, or even substandard housing facilities.^11,12,14 As more evidence connects water contamination to public health risks, the fear of unsafe drinking water continues to grow and more widespread water filtering, including fluoride, will become the standard.

How can health-care professionals regain the public’s trust by providing water fluoridation alternatives?

The absence of community water fluoridation may seem overwhelming for some, highlighting the need to explore alternative solutions. The lack of dental care, proper nutrition, and oral health education along with poor oral hygiene remain the main causes of dental decay.² Health-care professionals must lead the charge in addressing these critical areas to effectively reduce dental decay. By doing so, medical and dental professionals can restore confidence in their communities and play a crucial role by:

Screening for caries risk factors, myofunctional impairment, dry mouth, inflammatory diseases, mental wellness, and gut health, which all impact tooth decay.
Providing customized systemic fluoride options such as drops, tablets, or lozenges prescribed by a dentist or primary care physician for children aged six months to 16 years old (only recommended if there is less than optimal systemic fluoridation available).³
Providing topical fluoride options for caries prevention, especially for the at-risk or lower-income population in their communities. This includes fluoride varnishes along with prescription and over-the-counter fluoride products.
Encouraging alternative remineralizing therapies such as xylitol, hydroxyapatite, nanosilver, and arginine that can be used alone or with other fluoride-containing products.
Providing preventive treatments such as customized oral prophylaxis or periodontal treatments, dental sealants, and silver diamine fluoride where needed.
Educating patients on topical fluoride versus systemic fluoride, dental caries risk factors, pH buffering, nutrition, oral home care, the importance of sleep and exercise on improved health outcomes, and proper hydration with safe water.

Conclusion

The debate over water fluoridation highlights the complexities of public health initiatives and the need for a more personalized, targeted approach to combating dental decay. While systemic fluoride has proven benefits, it is crucial to focus on the populations who will benefit most while offering tailored treatments for others. Rather than clinging to a one-size-fits-all strategy, we could embrace a more customized approach that addresses the root causes of dental decay and empowers individuals to make informed decisions about their oral health. Only by refocusing our efforts can we truly make a lasting impact on dental health outcomes.

Editor’s note: This article first appeared in Clinical Insights newsletter, a publication of the Endeavor Business Media Dental Group. Read more articles and subscribe.