Fluoride and your Health

History

In the 1930's dentists noticed that in certain parts of the United States some people had unusual stains on their teeth. The teeth with these stains (later called dental fluorosis, read more about that below) also appeared to be less prone to tooth decay. They discovered that the stains were there because of exposure to high levels (1 ppm of greater) of naturally occurring fluoride in their drinking water. In these areas with naturally fluoridated water people had lower incidences of cavities than areas where the drinking water had very low or no detectable levels of fluoride. Researchers sought a level of fluoride that would reduce the severity of dental fluorosis to no more than mild cases, but also have the added benefits of reduced tooth decay. Many areas began adding fluoride to public drinking water in 1945. Besides public drinking water, fluoride is now added to toothpaste, mouthwash, tablets, gels/foam, floss, and even vitamins. It can also be found in beverages and food that were prepared with fluoridated water.

Statistics

The CDC reports that 66.2% of people in the United States receive fluoridated water through public water sources. Counties in each state add different levels of fluoride to the drinking water; these levels are usually around 1 ppm and are not to exceed 4 ppm. Some areas have very high levels of naturally occurring fluoride where the water is usually monitored to make sure the fluoride does not exceed levels of 4 ppm. Information on which counties add fluoride, and how much, to their drinking water can be found here: http://apps.nccd.cdc.gov/MWF/Index.asp.

Arguments FOR fluoride in drinking water

Fluoridation of drinking water has been hailed as one of the greatest achievements of public health by the CDC because it prevents tooth decay and tooth loss in children and adults despite socioeconomic factors and rates of dental care.⁽¹⁾ Many health, service, and professional organizations stand behind fluoridation as a safe and effective way to prevent tooth decay. Fluoride is relatively inexpensive and is reported as completely safe by the CDC. Fluoridation of public drinking water is about $0.50 per person per year in most communities. The American Dental Association says that fluoridation is a great investment; for every $1 spent on water fluoridation, $38 is saved on dental care.

Teeth with a mild case of fluorosis

While high exposure of fluoride may cause dental fluorosis, most cases are mild and barely visible; this is simply cosmetic and doesn't affect a tooth's function. Some of the earliest studies showed that water with fluoride reduced the total number of cavities in children's baby teeth by 60% and reduced tooth decay in permanent teeth by 35%.⁽²⁾ A 2010 study found that adults who were born in a city with fluoridated water experienced less tooth loss as an adult.⁽³⁾

Fluoride levels added to water in a small amount copies the natural phenomena of naturally occurring levels in places around the world. Fortifying water with fluoride is often compared to fortifying salt with iodine or adding vitamin C to juice or milk. Most water filters do not remove fluoride because it is often seen as a desirable addition to drinking water. Many communities have voted in favor of adding fluoride to public drinking water.

A recent study examined whether or not there was a relationship between fluoride exposure and osteosarcoma (a cancer that starts in the bones) risk. Their analysis showed no significant association of bone fluoride levels and the risk of osteosarcoma.⁽⁴⁾

Arguments AGAINST fluoride in drinking water

Many recent studies on fluoride have suggested the need for further studies to test whether or not fluoridation of water is actually necessary, and whether or not it may cause underlying health problems. It may be a possibility of the bad outweighing the good. We can see what happens to our teeth when we consume too much fluoride, but we can't see with the naked eye what too much fluoride does to our bones and other parts of our bodies. There may be fluoride dangers that are not known.

Topical uses of fluoride (like in toothpaste) that you don't ingest, does prevent cavities and is said to be safe, but more and more studies are finding that ingesting a lot of fluoride may be harmful to our health. Fluoride has been said to cause Alzheimer's, hypothyroidism, arthritis, bone cancer, hip/joint problems, brain developmental problems in children and more. While we are unsure if these claims are 100% true, they are concerning and suggest that we should think twice about adding fluoride to our drinking water until more studies prove its absolute safety. The EPA also stated that excessive exposure of fluoride (over 4 ppm) over a lifetime may cause bone fractures, bone pain/tenderness, and bone disease.⁽⁵⁾

While dentists say that dental fluorosis is simply a cosmetic concern, some studies correlate dental fluorosis with other issues. For example, many areas in China have high levels of naturally occurring fluoride in their water; studies have shown that children who had dental fluorosis also had lower IQ scores than children who did not exhibit signs of dental fluorosis.⁽⁶⁾ An American study that exposed animals to high levels of fluoride saw that fluoride accumulated in brain tissue possibly causing negative impacts on learning and memory.⁽⁷⁾

Data from the World Health Organization of fluoridated vs. unfluoridated countries from the years 1965-2005 show an overall trend in every country of a reduction in tooth decay. This suggests that water fluoridation is probably not responsible for the reduction of tooth decay.⁽⁸⁾

Others argue that the earlier studies administered on fluoride safety were conducted with the naturally occurring kind: calcium fluoride. Fluoride that is added to public drinking water is not calcium fluoride, it is fluorosilicic acid, sodium fluorosilicate, or sodium fluoride and are not from pharmaceutical grade sources. Instead these chemicals are by-products of fertilizer production and are often purchased from phosphate fertilizer companies. You can tell what type of fluoride is added to your public drinking water here: http://apps.nccd.cdc.gov/MWF/Index.asp.