What Is Fluoride, and Is It Safe?

Fluoride is found naturally in water, soil, and certain foods. It is vital to dental health. Fluoride is a recommended staple in many oral health products, like toothpaste and mouthwash, to help strengthen tooth enamel and prevent cavities.

Fluoride is also added to local water supplies in the United States to support dental health (water fluoridation). However, some concerns are raised about overexposure to the mineral.

This article discusses fluoride's dental health benefits, community water fluoridation, safety considerations, and potential side effects.

What Is Fluoride Used For?

Fluoride is used in oral and dental health. Research shows it's effective in preventing cavities.

Experts recommend brushing your teeth twice daily with fluoride toothpaste and drinking the recommended amounts of fluoridated water if available in your community.

What Are the Benefits of Fluoride?

Research shows that fluoride supports dental health in several ways, including:

• Strengthens and re-mineralizes tooth enamel: Fluoride does this by bonding to decay and attracting minerals like calcium.
• Protects against tooth decay: It triggers the production of protective tooth enamel that resists bacteria and acids.
• Contains antibacterial properties: Fluoride prevents harmful oral bacteria from growing and sticking to teeth.
• Plays a role in cavity reduction: While it can't eliminate existing cavities, it can help slow their rate of development.

Potential Side Effects From Fluoride

If consumed in excessive amounts, fluoride has some potential side effects to be aware of.

Dental Fluorosis

Dental fluorosis describes a change in tooth appearance in young children exposed to too much fluoride. It often looks like white spots or lines on the outer layer of the tooth enamel.

While fluoride is recommended in dental care for both children and adults, overuse can lead to dental fluorosis before permanent teeth are fully formed, which is usually before the age of 8. This is why adults do not develop dental fluorosis.

Dental fluorosis is typically mild and should not cause pain or permanently affect the way the teeth look or function. Moderate or severe cases of dental fluorosis that lead to extensive tooth enamel changes are considered to be rare.

Skeletal Fluorosis

Skeletal fluorosis is a rare condition in which fluoride builds up in the bones from ingesting high fluoride levels through the water supply over an extended period. This leads to changes in the bone structure, resulting in joint stiffness, weakened bones, and potential bone fractures.

The Environmental Protection Agency's (EPA) drinking water standard has set a maximum amount of fluoride for public drinking water systems—4 milligrams per liter of water (mg/L)—to help prevent skeletal fluorosis cases from occurring.

Is Fluoridated Water Dangerous?

Fluoride is naturally found in water but in varying amounts. Decades ago, researchers found that people in communities where the drinking water supply contained a certain level of fluoride had fewer dental cavities than those living in areas with lower fluoride levels in the water.

This is when the process of water fluoridation, which involves adding the mineral to the drinking water supply, began. Fluoride is added to reach at least 0.7 mg/L, which data shows is beneficial for oral health.

Although data show that drinking fluoridated water may help reduce cavities by up to 25% in children and adults, some have criticized the practice of widespread water fluoridation. Criticism has concerned the potential for excess fluoride intake, the possibility of contamination with other chemicals, and the chances of experiencing side effects in some cases.

Concerns have also been raised about a connection between fluoride exposure and bone cancer; however, experts generally agree that the evidence is not strong enough to make this link.

Experts suggest a recommended fluoride level for community water supplies, but state and local laws determine whether water fluoridation is implemented.

How Do I Know If My Water Is Fluoridated?

Each community's water supply is different. Tap water, well water, and even bottled water all contain varying amounts of fluoride.

Most tap water supplies contain fluoride at the recommended levels. Your local water supplier must complete an annual report on drinking water and can provide more information about the fluoride levels in your tap drinking water.

Well water fluoride content can be tested by laboratory analysis. Check with your local health department for directions on how to get your water sample tested.

Because bottled water comes from different public or natural water systems, you need to check the label or contact the manufacturer for information about the fluoride content. Some bottled water brands contain fluoride, while others may contain none or only trace amounts.

The Food and Drug Administration (FDA) sets bottled water standards with a maximum quantity of fluoride added to help control excessive consumption of the mineral.

Fluoride Safety

Not getting enough fluoride can result in cavities and weaker bones (including teeth).

While there isn't enough scientific evidence to set exact daily intake recommendations for fluoride, experts suggest general estimates of how much fluoride most people need to maintain adequate nutrition. The daily amounts include:

• Infants: 0.01–0.5 mg
• Children: 0.7–2 mg
• Teenagers: 3 mg
• Male adults: 4 mg
• Female adults: 3 mg

Data suggest that it's rare for adults to get too much fluoride. But to help ensure that babies and children are not consuming excess fluoride, experts recommend the following:

• Avoiding fluoride toothpaste in babies younger than 2
• Using a pea-sized amount of fluoride toothpaste for children ages 2 and older
• Avoiding fluoride mouthwash in children younger than 6
• Discussing with your healthcare provider before using any fluoride supplements
• Making sure children under the age of 8 are not getting too much fluoride from drinking water

Check with your healthcare provider about the best type of water to use in baby formula.

Summary

Fluoride protects against cavities by strengthening teeth and controlling plaque. It is a recommended ingredient in dental products like toothpaste and mouthwash and is also added at safe levels to community water supplies to support oral health.

While some concerns have been floated about the potential side effects of overexposure to the mineral, research shows that fluoride is beneficial when consumed in recommended amounts. It's especially important that babies and children do not ingest too much fluoride. Always check with a healthcare or dental provider if you have questions about the fluoride content in products or water.