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Is the fluoride in water good for your teeth?

The Fluoride Controversy

Not everybody believes fluoride is good for the community. In fact, some people believe that fluoride is a carcinogen. But before we get into the health controversies about fluoride, we should point out that the National Cancer Institute (NCI) has taken a formal stance on the matter: After numerous studies and research, NCI finds no proof of increased cancer risk associated with fluoridated water [source: NCI]. Also, a 1999 report by the Centers for Disease Control and Prevention (CDC) reported "no credible evidence" that fluoridated water causes cancer [source: NCI].

Much of the anti-fluoride movement banks on a study done on rats in 1987. Two Boston researchers found that, after adding fluoride to lab rats' drinking water, some curious things happened: Female rats that happened to be pregnant gave birth to "hyperactive" babies. When the baby rats were given fluoridated water, they exhibited signs of cognitive disorders. It's important to note that the rats were given a higher fluoride concentration than most people receive in their drinking water -- five parts per million (ppm) per the normal one ppm. However, advocates of the research point out that much of the population also ingests more fluoride than what's in the drinking water -- for example, some athletes and children take fluoride supplements [source: Bryson].

Some chemists argue that fluoride is as toxic as arsenic at the one ppm concentration [source: Mercola]. They also point out that the warnings on the back of a tube of fluoride toothpaste recommend calling poison control if a child swallows more than a pea-sized amount of toothpaste. And yet, they argue, a child drinks several glasses of fluoridated water a day.

In the past, fluoride was also used to decrease thyroid function -- as a treatment for people with overactive thyroid glands -- which brings up the question of whether ingesting the fluoride in water leads to an underactive thyroid. Scientists are working to find an answer.

Opponents of fluoridated drinking water advise against using tap water to make infant formula and recommend using non-fluoridated bottled water instead. Of course, the only person that can make these decisions is you. Your best bet is to stay educated, and no matter what, remember to brush and floss every single day.

For more about oral hygiene, check out the links on the next page.