What Is Fluoride? What Does Fluoride Do?

Fluoride is a chemical ion of the element fluorine (from the Latin fluo meaning "to flow"), in that fluoride has one extra electron that gives it a negative charge. Fluoride is found naturally in water, foods, soil, and several minerals such as fluorite and fluorapatite. However, it is also synthesized in laboratories where it may be added to drinking water or used in a variety of chemical products.

Fluoride is most commonly associated with dental hygiene products and tooth protection. Most people are exposed to fluoride through treated drinking water or products such as toothpaste and mouthwash.

What does fluoride do?

Fluoride protects teeth from decay and cavities in two ways. When bacteria in the mouth combine with sugars, acid is produced that can erode tooth enamel and damage teeth. Fluoride can protect teeth from demineralization that is caused by the acid. If teeth have already been damaged by acid, fluoride accumulates in the demineralized areas and begins strengthening the enamel - a process called remineralization. Fluoride is very useful for preventing cavities and strengthening teeth, but its effectiveness is thwarted if a cavity has already formed.

How is fluoride obtained?

Fluoride may be ingested or applied topically. If foods containing fluoride (such as meat, fish, eggs, and tea leaves) are consumed, then fluoride enters the bloodstream and is eventually absorbed by the teeth and bones. Many communities add fluoride to the drinking water to ensure that the recommended levels are obtained.

Fluoride can also be applied directly to teeth by a professional in a dental office. The teeth will readily absorb topical fluoride treatments, and the chemical will remain in the mouth for several hours. Less thorough topical fluoride treatments may also be applied at home using products such as toothpaste, mouthwash or mouth rinse, fluoride gels, or fluoride supplements.

Who needs fluoride?

Many governmental health agencies recommend that both children and adults receive some level of fluoride. Children need fluoride to protect their permanent teeth as they are forming. Adults need fluoride so that they can continue to protect teeth against tooth decay. Several groups of people could benefit especially from fluoride treatments because they have a higher risk of tooth decay. This includes people who have:

• A history of cavities or tooth decay
• No or little access to dentists
• Poor dental hygiene
• Diets with high amounts of sugars or carbohydrates
• Snacking habits
• Braces, crowns, bridges, and other teeth restoration procedures
• A lack of saliva or dry mouth

Is fluoride safe?

When used properly, fluoride is usually considered a safe and effective tool to prevent tooth decay. However, high levels of fluoride exposure for extended periods of time may result in harm. For example, dental fluorosis - a discoloration of tooth enamel - may occur if a person is exposed to too much fluoride. In addition, it is possible for a lifetime of exposure to high fluoride levels to lead to bone weakening and skeletal fluorosis (joint stiffness and pain).

More extreme, toxic effects and even death may result if someone consumes too much fluoride. Fluoride overdose is possible, for example, if a small child consumes an entire tube of tooth paste. Symptoms include nausea, vomiting blood, diarrhea, stomach pain, salivation, watery eyes, general weakness, shallow breathing, faintness, tiredness, and convulsions.

Why is fluoride controversial?

Although scientific research has supported the benefits of fluoride treatment in preventing tooth decay, many people question its safety and effectiveness. Several interest groups cite recent increases in dental fluorosis and fluoride levels in water that exceed optimal levels in calling for an end to fluoridated drinking water. They deem fluoride treatments unnecessary and less useful and more dangerous than originally thought.