Fluoride in Drinking Water and Its Potential Effects

Updated: January 12th, 2023

If you live in the United States, there’s a good chance that your tap water contains fluoride. Yup, the very same fluoride found in most kinds of toothpaste, mouthwash, and other dental products.

The U.S. began adding fluoride to some public water supplies in the 1940s as a public health measure to reduce incidences of cavities among the population. Evidence shows that fluoride helps to:

  • rebuild weakened tooth enamel
  • slow down the loss of minerals from tooth enamel
  • reverse early signs of tooth decay
  • prevent the growth of harmful bacteria in the mouth

It’s no wonder why about two-thirds of the country’s population has fluoridated public water, according to the Centers for Disease Control and Prevention (CDC).

Not everyone supports water fluoridation, though. The practice has sparked outrage among many Americans, including the general public, environmental activists, pregnant women, mothers, and other groups, calling for a nationwide ban on adding fluoride to public drinking water.

Some people argue that fluoride is a neurotoxin that is harmful to thyroid, brain, and bone. They also claim that, when ingested, the mineral may present certain health risks (which we’ll be discussing in this article).

There’s also a strong belief that since fluoride can be obtained from multiple sources, including toothpaste and dental rinses, there’s no need to add it to drinking water – or at least, people should have the freedom of choice.

While we recognize that fluoride has many remarkable benefits, we must also explore the potential health effects of ingesting it in high amounts. So, without further delay, let’s get right into it.

What is fluoride?

Fluoride is a naturally-occurring mineral in soil, water, foods, and the human body in bones and teeth. It helps to strengthen teeth and fight against tooth decay. Because of this, it is added to many over-the-counter dental products (like toothpaste, mouthwash, and dental supplements) and public drinking water supplies.

How are people exposed to fluoride?

The primary mediums through which people are exposed to fluoride are the diet (food, water, beverages) and fluoride-containing dental products (toothpaste, mouth rinse, fluoride supplements). Internal exposure to fluoride may also occur from inhalation (cigarette smoke, industrial emissions), dermal absorption (from chemicals or pharmaceutics), ingestion or administration of fluoride-containing drugs, and ingestion of fluoride-containing soil.

Let’s take a closer look at the three most common ways people are exposed to fluoride:

Drinking water

Since fluoride is ubiquitous in the environment, almost all water sources contain a small amount of the mineral. Of course, the amount of fluoride contained in these non-fluoridated sources depends on the individual geological environment from which the water is obtained. Levels of fluoride in water may range up to 2.0 mg/liter. Still, in areas where skeletal fluorosis and teeth fluorosis were well reported, fluoride levels may range from 3 mg/liter to over 20 mg/liter. In areas where fluoride is intentionally added to drinking water, the concentration of the mineral typically ranges from 0.7 to 1.2 mg/liter.


Almost all kinds of food contain at least trace amounts of fluoride. Fish are particularly rich in fluoride. Tea leaves also contain elevated levels of fluoride. However, the mineral’s concentration in brewed tea depends on the concentration of soluble fluoride in the tea leaves, the amount of fluoride in the water used to prepare it, and the length of the brewing period. The concentration of fluoride in some foods significantly increases when super phosphate fertilizers are added to agricultural soil. These types of fertilizers usually contain significant amounts of fluoride.

The level of fluoride in food is primarily affected by the fluoride content of the water used in preparation or processing, most notably in beverages and dry foodstuff – like powdered baby formulas – to which water must be added before consumption. In commercially available infant formulas sold in the U.S., soy-based, instant liquid concentrate formulas contain higher fluoride levels than the equivalent milk-based products. Fluoride has also been detected in breast milk.

Toothpaste and other dental products

Dental products, such as toothpaste, mouthwash, and fluoride supplements, have been identified as significant sources of fluoride. Mouth rinses that are marketed for daily home use usually contain between 230 and 1,000 mg/liter of fluoride. In contrast, mouthwash products intended for weekly or biweekly use may contain 900 to 1,000 mg/liter of the mineral.

How much fluoride do people consume a day?

Individual exposure to fluoride is highly variable. Inhaling airborne fluoride generally makes a small contribution to the total intake of the mineral. But for adults, the consumption of fluoride-containing food and drinking water is the primary medium for fluoride intake.

In areas where coal rich in fluoride is used for heating and food preparation, inhaling indoor air and consuming food containing increased fluoride levels also contribute to elevated intakes.

Infants that are fed formula consume 50 to 100 times more fluoride than infants that are breastfed exclusively. When young children ingest toothpaste or any other substance, such as powder for cleaning the teeth, it significantly increases their exposure to fluoride. Generally, the estimated fluoride intake in children does not exceed 2 mg/day. Although adults may have a higher daily intake of fluoride in milligrams, the daily intake of fluoride by children may exceed that of adults due to the amount of fluoride ingested relative to their body weight.

In certain areas where fluoride concentration in the surrounding environment is excessively high or where diets include foods that are rich in fluoride, it’s reported that the estimated fluoride intake in adults is high as 27 mg/day. The leading cause for this elevated fluoride intake is none other than drinking water obtained from groundwater sources located in fluoride-rich geological areas. Yup, you guessed it.

Are high levels of fluoride in drinking water dangerous?

While fluoride is a naturally-occurring mineral, ingesting too much of it can cause several mild to severe side effects. There’s sufficient evidence that suggests that a small dose of fluoride can help prevent cavities. But despite that, some children in the U.S. are exposed to elevated levels of fluoride that may lead to various adverse health effects.

Health conditions linked to too much fluoride include:

Dental fluorosis

Dental fluorosis is a condition that affects the enamel of the tooth. It is caused by overexposure to fluoride during the first eight years of life when your teeth are still forming under your gum. The severity of the condition may range from mild tooth discoloration to severe yellow to dark brown staining, to enamel erosion, to pitting. Dental fluorosis tends only to affect children up to 8 years old who have permanent teeth still coming in and are overexposed to fluoride.

According to some health experts, over 5 million Americans suffer from moderate to severe dental fluorosis, with the highest rates believed to be among adolescents. Besides, the U.S. Health Service lowered its recommended levels of fluoride in drinking water after roughly 50 years to address an increasing prevalence of dental fluorosis in young people.

Skeletal fluorosis

Skeletal fluorosis is somewhat similar to dental fluorosis, but it affects the bones instead of the teeth. It is a condition in which excessive fluoride accumulates in the bone tissue, which can lead to problems like joint pain, fractures, stiffness, and osteosclerosis. However, over time, it can alter the bone structure, potentially leading to crippling deformities of the spine and joints. It can also cause calcium to build up in the soft tissue in the ligaments, causing them to harden. The more severe forms of skeletal fluorosis typically come with long-term exposure to unusually high fluoride levels, often in drinking water.

Lower IQ scores in boys

Several studies have raised concerns about a possible link between increased fluoride exposure during pregnancy and lower IQ in young children, specifically in boys. Scientists observed that an increase of 1 mg/liter of fluoride in the urine of mothers predicted a drop in IQ of 4.5 points in young boys 3 to 4 years. However, when the same test was done on mothers who had daughters, no link was found between fluoride and decreased IQ.

Higher risk of neuro developmental disorders:

According to researchers at CFAH and York University, higher levels of urinary fluoride during pregnancy are linked to more ADHD-like symptoms in school-age children. The findings show that children with elevated prenatal exposure to fluoride were more likely to exhibit ADHD symptoms, as reported by parents. The research also found that prenatal fluoride exposure was more strongly associated with inattentive behaviors and cognitive problems, but not with hyperactivity.

Who regulates fluoride in drinking water and what are the limits?

Adding fluoride to all drinking water sources is not mandatory in the U.S., but thankfully, the levels of fluoride in water are regulated by several government agencies.

The regulation of fluoride in water supplies began in 1962 when the United States Public Health Service (PHS) recommended that public water supplies contain anywhere between 0.7 and 1.2 mg/liter of fluoride. This range was the optimal level at which fluoride was believed to be sufficient to provide the best protection against tooth decay and other dental dilemmas while limiting the risk of dental fluorosis. However, that initial recommendation was updated in 2015 to a fluoride level of 0.7 mg/liter based on several considerations that include:

  • The increased availability of fluoride from several sources other than drinking water
  • Trends in the prevalence and severity of dental fluorosis
  • Scientific evidence related to the effectiveness of water fluoridation in preventing caries and control across all age groups, and
  • The current evidence on the fluid intake of children across various outdoor air temperatures

The United States Environmental Protection Agency (EPA) also introduced its own set of regulatory rules for fluoride in drinking water. The agency has set a maximum amount of fluoride allowable of 4.0 mg/liter. Long-term exposure to levels higher than this can lead to several different health conditions. The EPA has also set a secondary standard of no more than 2.0 mg/liter to help protect children (under the age of 9) from dental fluorosis and other complications. This secondary standard is only a guideline, but public water systems must inform customers if the fluoride level goes above it.

How to reduce your exposure to fluoride in tap water

Even without adding fluoride to water, the natural levels of the mineral in some places may exceed the recommended 4 mg/liter. Community water systems in such areas are required to lower the fluoride level below the acceptable standard. However, the levels in private water sources, such as wells, may still be higher.

If you are concerned that you or your family may be exposed to too much fluoride, here are a few steps you can take to reduce your exposure:

Know if and how much fluoride is in your drinking water:

If your water comes from a public source, you can check how much fluoride is in your drinking water by contacting your local community water provider. People who get their drinking water from private sources, such as wells, can have their fluoride levels tested by a reputable laboratory, or check it themselves with a home water testing kit.

Every water provider is also required to provide customers with an annual water quality report, also known as a Consumer Confidence Report. This report contains information about the levels of certain chemicals and other pollutants in the water, including fluoride.

Install a reliable and efficient water filtration system:

If you live in an area with high fluoride levels in your water, you might be tempted to use bottled water as an alternate source. If that’s the case, it’s better to choose filtered water instead. You can filter fluoride out of your drinking water by installing a good-quality water filtration system.

Water filtration systems are specifically designed to remove all kinds of contaminants and impurities from water. That way, you and your family can enjoy clean, refreshing, contaminant-free water, while reducing or eliminating the risks of diseases and illnesses.

Reverse osmosis (RO) filters, like the Springwell SWRO-Nickel and the Springwell SWRO-Bronze under-sink systems, are the most popular and most reliable solutions for filtering out fluoride from your drinking water. Both models are point-of-use systems, which means you can filter fluoride at specific areas in your house where you consume water. Best of all, they are compact and can fit comfortably under almost any sink and away from immediate view.

Our reverse osmosis systems use a semi-permeable membrane to filter out even the tiniest of contaminants from water and can effectively remove up to 98% of fluoride from your drinking water. The sediment filter included in both systems can filter contaminants down to 5 microns. In addition, the semi-permeable membrane has pores that are large enough to allow water molecules to pass through but small enough to block other types of particles down to 0.001 microns in size. And if that wasn’t enough, the SWRO-Nickel and the SWRO-Bronze produce up to 75 gallons of filtered water per day.

When you purchase any of these or any other water filtration systems from Springwell, you get a lifetime warranty, a six-month money-back guarantee, and free shipping! Plus, if you cannot cover the system’s full price upfront, you can finance it with affordable monthly payments up to a year.

If you’re ready to eliminate fluoride from your drinking water once and for all, contact us to find the best option to achieve that and more.

Final Thoughts

Fluoride is a naturally-occurring mineral used in many dental products to strengthen tooth enamel and fight off cavities. It’s also added to many public water supplies in America, a move that has stirred up some controversy about the mineral’s potential effects on human health.

While the amount of fluoride added to drinking water is regulated and considered safe, exposure to high levels of the mineral may be linked to several adverse health effects. Thankfully, though, if you’re concerned about your fluoride intake, you can take a few steps to address your concerns. You can ask your local water provider about the fluoride in your city’s water, opt for fluoride-free dental products, or install a quality water filtration system from Springwell to eliminate fluoride from your drinking water at home.