For years I have been concerned with fluoride in our drinking water. I just don't like the fact that it is there and I haven't found a water filtration system that filters it out (at least, not one that I can afford). Contrary to previous belief, fluoride has minimal benefit when swallowed. According to the Centers for Disease Control, fluoride's "predominant effect is posteruptive and topical". Meaning, any benefits that accrue from the use of fluoride, come from the direct application of fluoride to the outside of teeth (after they have erupted into the mouth) and not from ingestion. There is no need, therefore, to expose all other tissues to fluoride by swallowing it. Yes, we continue to drink our city water, which is fluorinated, but I am not happy about it.
Once I turned 18 I stopped getting fluoride treatments on my teeth during a cleaning at the dentist office and have never had my children get them. The main reason for it is because I have dental fluorosis (which is now estimated to affect around 30% of American children and adults), which is the first visible sign of excessive fluoride exposure. It results in whitish or dark flecks and spots on the teeth. I have been able to get them bleached (at $200 a pop) but only did that once, as they come back due to not being stains, but rather marks on and in the teeth. I don't want my children to get that and it just proves that fluoride isn't exactly a good thing.
We go in spurts when we buy fluorinated toothpaste and unfluorinated. My husband seems to have very thin enamel and tends to get cavities when we use the unfluorinated toothpaste. The children typically use the unfluorinated and we have just had to deal with one cavity in my daughter, which I doubt is due to the lack of fluoride but more to the fact that I have started to let her brush her own teeth and I think she didn't do such a great job. I am not as worried about the toothpaste as it is not ingested.
There are other health affects of fluoride than just the dental fluorosis. According to the National Research Council (NRC), fluoride can damage the brain. Animal studies conducted in the 1990s by EPA scientists found dementia-like effects at the same concentration (1 ppm) used to fluoridate water, while human studies have found adverse effects on IQ at levels as low as 0.9 ppm among children with nutrient deficiencies, and 1.8 ppm among children with adequate nutrient intake.
People with kidney disease have a heightened susceptibility to fluoride toxicity. The heightened risk stems from an impaired ability to excrete fluoride from the body. As a result, toxic levels of fluoride can accumulate in the bones, intensify the toxicity of aluminum build-up, and cause or exacerbate a painful bone disease known as renal osteodystrophy.
According to the NRC, fluoride is an endocrine disruptor. Most notably, the NRC has warned that doses of fluoride (0.01-0.03 mg/kg/day) achievable by drinking fluoridated water, may reduce the function of the thyroid among individuals with low-iodine intake. Reduction of thyroid activity can lead to loss of mental acuity, depression and weight gain.
Less known to the public is that fluoride also accumulates in bones. It increases the risk for bone fracture and has even been linked to a serious form of bone cancer (osteosarcoma).
Fluoride hasn't even been proven to be the direct link to prevent cavities. No difference exists in tooth decay between fluorinated & unfluorinated countries.
We do try to avoid fluoride as much as possible.