Updated: July 12, 2019
Fluoride is a mineral renowned for strengthening teeth helping to prevent cavities and related diseases. Fluoride is a form of the chemical element fluorine. It is used as medicine.
Fluoride protects teeth from the bacteria in plaque. It also promotes new bone formation. This is different than most medicines used for weak bones (osteoporosis), which fight osteoporosis by keeping bone from being broken down. Fluoride can be administered in different ways, either topically (toothpastes, mouth rinses, varnishes, gels) or systemically (fluoride supplements, fluoridated water, salt). Posteruptive (topical) preventive effect of fluoride is considered as being more important than the pre-eruptive (systemic) effect. Topical fluorides have been shown to be highly effective and the use of fluoride-containing toothpastes is now almost universal. When daily toothbrushing with a fluoridated toothpaste is not carried out or when the caries-risk is increased, additional sources of fluoride could be recommended.
Fluoride is added to public drinking water to prevent tooth decay. Children who do not drink fluorinated public water because their homes use water from a private well often take fluoride tablets to prevent tooth decay. Fluoride is added to toothpaste and mouthwashes so it can be applied directly to the teeth to prevent tooth decay. Fluoride is also taken by mouth for treating weakened bones (osteoporosis) and for preventing bone loss in people with rheumatoid arthritis and Crohn's disease. Fluoride supplements are administered in the form of lozenges, tablets or liquids.
Fluoride tends to get concentrated in tea, coffee, shellfish, grapes (raisins, wine, grape juice), artificial sweeteners, sodas, potatoes, flavored popsicles, baby foods, broths, stews, and hot cereals made with tap water. Of these water, tea, coffee, shellfish, potatoes, and grapes can be considered healthy. All other sources should be avoided.
Further sugary or carbonated drinks can lead to more tooth decay, wiping out any good effect from the fluoride. For all these fluoride foods and drinks, if fluoride fortified water was used in their creation, they will have even more fluoride.
Most fresh foods and fresh water contains very little fluoride. Therefore, one will receive very little fluoride when drinking spring water and eating unprocessed fruit, vegetables, grains, eggs, milk, and meat. However, there are some exceptions to seafood, tea, water from deep wells, and fresh fruit/vegetables sprayed with fluoride pesticides. Here is a list of source of fluoride:
Tea plants absorb fluoride from the soil. As a result, tea leavesâparticularly old tea leavesâcontain high levels of fluoride. Brewed black tea averages about 3 to 4 parts ppm fluoride, while commercial iced tea drinks contain between 1 and 4 ppm. As a result of these elevated levels, there is a link in excessive tea consumption to a bone disease (skeletal fluorosis) caused by too much fluoride intake. Also The amount of fluoride the tea contains will depend on the water used to prepare it. Even commercial teas sold in bottles and cans will contain some fluoride.
Even if you don't live in a community that adds fluoride to its water supply, you will still be exposed to fluoridated drinking water. This is because once fluoride is added in mass to water it winds in almost all processed beverages and foods. In the U.S., studies have shown that sodas, juices, sports drinks, beers, and many other processed foods, including infant foods, now have elevated fluoride levels.
Many dental products now contain fluoride, including over 95% of toothpaste. Studies show that a significant number of children swallow more fluoride from toothpaste alone than is recommended as a total daily ingestion.
Due its toxicity, fluoride is used in some pesticides to kill insects and other pests. As a result of fluoride pesticide use, some food products particularly grape products, dried fruit, dried beans, cocoa powder, and walnuts can have high levels of fluoride.
Foods made with mechanically separated meat (e.g., chicken fingers, nuggets, etc), contain elevated levels of fluoride due to the contamination from bone particles that occurs during the mechanical deboning processed. Mechanically processed chicken meats have the highest levels, with chicken sticks containing an average of 3.6 ppm.
Cooking food, or boiling water, in teflon pans may increase the fluoride content of food. In one study, it was found that boiling water in a teflon pan for just 15 minutes added an additional 2 ppm of fluoride to the water, thus bringing the final concentration to 3 ppm.
Many pharmaceuticals are fluorinated, meaning they contain a carbon-fluorine bond. Although the carbon-fluoride bond in most drugs is strong enough to resist breaking down into fluoride within the body, this is not always the case as research has found that some fluorinated drugs, including cipro, do break down into fluoride and can thus be a major source of fluoride exposure for some individuals.
Fluoride is a common air contaminant in industrial workplaces. As a result, workers in many heavy industries including the aluminum, fertilizer, iron, oil refining, semi-conductor, and steel industries can be routinely exposed to high levels of fluoride exposure. In addition they will also have a significant risk factor for respiratory disease; airborne fluorides can be a huge daily source fluoride intake.
When fluoride is added to drinking water or included in toothpastes, mouthwashes, and other dental products, it is effective in preventing tooth decay.
Fluoride taken by mouth continuously or cyclically (three months on, one month off) might increase bone mineral density, which is an indicator of bone strength. Fluoride seems to work better for improving bone strength in older women when combined with hormone replacement therapy. However, itâs not clear whether taking fluoride actually reduces the chance of weak bones breaking.
More evidence is needed to rate the effectiveness of fluoride for these uses.
Fluoride is safe for most people in the amounts added to public water supplies and used in toothpastes and mouthwashes, and applied by dentists. Low doses (up to 20 mg per day of elemental fluoride) of supplemental fluoride taken by mouth appear to be safe for most people.
Higher doses are unsafe and can weaken bones and ligaments, and cause muscle weakness and nervous system problems. High doses of fluoride in children before their permanent teeth come through the gums can cause tooth discoloration. Toothpaste and fluoride rinses should not be swallowed routinely, particularly by children. It is a good idea to make sure that children under six years of age use only a pea-sized amount of fluoride-containing toothpaste, just in case they swallow some.
Fluoride seems to be safe during pregnancy and breast-feeding when taken in doses below the tolerable upper intake level (UL) of 10 mg per day of elemental fluoride and when applied directly to the teeth in toothpastes and mouthwashes. But higher doses are unsafe and can weaken bones and ligaments, and cause muscle weakness and nervous system problems.
According to the National Library of Medicine (NLM), the amount of fluoride you need depends on your body mass (weight).
The following doses have been studied in scientific research and is recommended:
In the US, fluoride is added to city water to a concentration of 0.7 to 1.2 parts per million (ppm).
To prevent dental caries in areas where the fluoride level in drinking water is less than 0.3 ppm (such as in well water),
For children living in areas where the fluoride level is 0.3 to 0.6 ppm,
No supplement is needed in areas where the fluoride in drinking water exceeds 0.6 ppm.
15 to 20 mg per day of elemental fluoride.
The daily Adequate Intakes (AI) for elemental fluoride from all sources including drinking water are:
The daily upper intake levels (UL) for fluoride, the highest level at which no harmful effects are expected, are
Sodium fluoride contains 45% elemental fluoride. Monofluorophosphate contains 19% elemental fluoride.