Through the course of my career, I've run across a plethora of opinions regarding fluoride. Some people swear by it, others avoid it like the plague, and the CDC has heralded it as one of the top 10 public health achievements of the 20th century. So why the rift in public opinion?
Let's begin by stating the major point of opposition for use of fluoride - fluoride is toxic to humans when ingested at high doses. Excessive long-term doses of fluoride can affect tooth formation, bone composition, neurological development, and thyroid issues, while concentrated acute doses can cause nausea, abdominal pain, excessive salivation, muscle spasms, and potentially seizures.
Now that we got that out of the way, let's talk real life application and risk. In the United States, the maximum recommended intake of fluoride is 10 mg/day. The most common ingested source of fluoride is our tap water, which is generally distributed to the masses at a dosage of 1 ppm. That means an adult would have to drink 10 liters, or 2.64 gallons, of fluoridated water to reach the daily maximum allowable amount. Practically speaking, you'd have to make a serious effort and drink potentially dangerous amounts of tap water to reach unsafe levels of fluoride. Fluoride is also found naturally in some of our foods, such as raisins, black tea, wine, potatoes, among many other food types, but these levels are relatively inconsequential with regards to human safety. Toothpaste has concentrated fluoride in it, generally ranging from 1,000 ppm to 1,500 ppm for over-the-counter toothpaste and 5,000 ppm for prescription-strength toothpaste.
Unless you're using it incorrectly, this type of concentrated fluoride is not being ingested, so the risks of harmful dosage of fluoride in toothpaste is negligible. If you want to eliminate the risks of fluoride ingestion, rather than seek out non-fluoridated toothpaste, avoid using tap water for drinking or cooking. The implications for using fluoride in modern dentistry is scientifically based and has been proven to be safe for humans. The purpose of fluoride is to remineralize teeth that have been demineralized by bacterial accumulation in the mouth. Cavities do not just appear all of a sudden - the cavitation process usually is fairly long, and with proper early intervention, the process can be halted. Often times the dentist or dental team will recommend or offer fluoride varnish, which is a hyper-concentrated fluoride solution (22,000+ ppm) applied directly to the teeth to provide an immediate, strong response to demineralization. Halting progression of cavities is essential to preserving natural tooth structure and establishing a healthy oral environment. If you are still opposed to using fluoride toothpaste or varnish, the best recommendation for maintaining your oral health is meticulous home care with appropriate brushing and flossing. Drinking adequate amounts of water and stimulating saliva flow using xylitol-containing gum such as Trident also helps in reducing risk for developing cavities.