Fluoride is a naturally occurring mineral found in rocks and soil that helps prevent tooth decay. Over the last 70 years, small amounts of fluoride have been added to drinking water, toothpaste, mouth rinses, and professional dental materials to help strengthen tooth enamel.
Once ingested, your blood absorbs the mineral through the digestive tract and collects in the bones and teeth. In young children, it is especially useful in preventing dental caries (cavities). This is because baby tooth enamel is thinner and more susceptible to decay.
Since the introduction of added fluoride, there has been a dramatic decrease in dental caries in children and adults.
Concerning cavity prevention, there are three main benefits of fluoride:
Water fluoridation is the foundation of cavity prevention in children and adults. Fluoride is the most efficient way to strengthen tooth enamel, reduce tooth decay, and improve overall dental health within communities.
Some communities in the United States have natural sources of fluoride. However, most municipal water sources add the mineral into tap water as a public health measurement. The optimal level of fluoride concentration in drinking water has been determined by The Department of Health and Human Services (DHHS) to be 0.7 parts per million (ppm).
The amount of fluoride in water depend on the depth where the water is found and how many fluoride-bearing minerals are present in the area. For example, water supplies in the southwestern and midwestern sectors of America have high levels of natural fluoride, while low-income areas typically have low levels.
Proper water fluoridation is backed by over 70 years of research. It is safe, effective, and healthy. Moreover, the mineral is cost-saving, cost-effective, and reliable. Many national and international organizations including the World Health Organization (WHO), American Medical Association (AMA), American Dental Organization (ADA), and U.S. Centers for Disease Control and Prevention (CDC) support the fluoridation of public water supplies.
Studies have shown that fluoride reduces the risk of decay by up to 50 percent in primary (baby) teeth and up to 65 percent in permanent teeth of children exposed to water with proper levels of fluoride since birth.
The Centers for Disease Control and Prevention (CDC) has a Water System Information Tool that will provide you with information about your community water system including the fluoride content of your community.
Since the mineral is a highly toxic substance on its own, excessive consumption can cause a range of adverse health effects. For example, common conditions include:
Excess fluoride intake from water with more than 0.7 ppm of fluoride can cause dental fluorosis. In short, fluorosis is the hypomineralization of tooth enamel, which leads to abnormal enamel development and the formation of white streaks, yellow stains, or brown stains on teeth.
Excessive fluoride exposure can also lead to skeletal fluorosis, which damages the parathyroid glands (glands in the neck that control calcium levels). Further, the condition may cause joint stiffness, joint pain, weak bones, or fractures in older adults.
According to the International Association of Oral Medicine and Toxicology (IAOMT), an organization against added fluoride, long-term exposure may be linked to other health conditions, including:
The effects of fluoride are either topical or systemic:
Topical effects are obtained through the use of fluoride toothpaste, mouth rinses, and other concentrated forms of the mineral that are used at home or professionally in a dentist’s office. It also strengthens teeth and makes them less susceptible to decay-causing bacteria.
Dentists recommend this type of treatment for children's teeth between 3 and 6 years of age. Adolescents, teens, and adults also benefit from topical treatment. This includes self-applied toothpaste and professionally applied treatments, such as gels, pastes, and varnishes.
You can use self-applied fluoride dental products at home every day. The most common forms include toothpaste and mouthwash:
Fluoridated toothpaste is the most popular form of self-applied fluoride in the world. Fluoride toothpaste is available over-the-counter. Children and adults should brush their teeth with fluoridated toothpaste twice a day for optimal protection. Parents should also consult their child's dentist about the use of fluoridated toothpaste if they are under two years old.
Children under six years of age should only use only a pea-sized amount of toothpaste every time they brush to prevent dental fluorosis.
Similar to fluoridated toothpaste, rinsing with mouthwash reduces the chance of decay in children and adults. The most common compound used in mouth rinse is sodium fluoride, which is retained in saliva, reduces dental plaque, and ultimately helps prevent tooth decay.
Unlike self-applied treatments, professional topical treatments are completed in a dentist’s office at least twice a year:
Professional foams, rinses, and gels contain more fluoride than self-applied toothpaste and mouthwash. Although, since this treatment is only necessary a few times a year, fluoride gel poses little risk for dental fluorosis, even for patients under 6 years of age.
Professional treatment is typically beneficial for people who have a high risk of tooth decay. Those living in areas with low water fluoridation and patients who do not brush with fluoridated toothpaste also benefit from this treatment.
Systemic effects are obtained through the ingestion of liquids with natural fluoride levels, including water that contains natural fluoride and water with added fluoride. Patients can also obtain fluoride supplements (tablets). In addition, supplemental fluoride is commonly prescribed to children between 6 months and 16 years of age who live in areas with drinking water low in fluoride or those with a high risk for tooth decay.
In essence, systemic forms of the mineral help form tooth structure and provide topical protection against tooth decay.
Fluoridation Facts. American Dental Association, 2018.
Fluoride: Topical and Systemic Supplements, www.ada.org/en/member-center/oral-health-topics/fluoride-topical-and-systemic-supplements.
“Fluoridation FAQs.” Fluoridation FAQ, www.ada.org/en/public-programs/advocating-for-the-public/fluoride-and-fluoridation/fluoridation-faq.
Nowak, Arthur J. Pediatric Dentistry: Infancy through Adolescence. Elsevier, 2019.
Recommendations for using fluoride to prevent and control dental caries in the United States. Centers for Disease Control and Prevention. MMWR Recomm Rep 2001;50(Rr-14):1-42.
The American Dental Association (ADA). 5 Reasons Why Fluoride in Water Is Good for Communities. www.ada.org/en/public-programs/advocating-for-the-public/fluoride-and-fluoridation/5-reasons-why-fluoride-in-water-is-good-for-communities.
Environmental Protection Agency (EPA). Six-Year Review of Drinking Water Standards. 27 Feb. 2020, www.epa.gov/dwsixyearreview.