What is fluoride?
In nature, the element fluorine exists as a negatively charged
atom or ion. Thus, similar to iodide (iodine) and chloride (chlorine),
we commonly refer to fluorine as fluoride (F–). Fluoride salt (NaF)
is routinely added to toothpaste.
What are fluoride sources in the human diet?
Most foods are poor sources of fluoride and probably should not be used exclusively to meet the human body’s needs. However, the process of adding fluoride to drinking water (fluoridation) has greatly improved general fluoride consumption. However, the decision to use fluoride is not federal; it is regulated county by county in the United States.
What are current recommendations for fluoride intake?
The RDA for fluoride is 3 and 4 mg for adult women and men. During pregnancy and lactation the RDA is maintained at 3 mg daily.
What does fluoride do in the body?
Earlier in this century it was recognized that people living in regions of the United States where the fluoride content in their water supply was relatively high had a much lower incidence of dental caries. From this it was realized that fluoride is important to protect the teeth against the development of cavities. Fluoride may function in part by associating with hydroxyapatite in teeth and, to a lesser degree, bone.
What happens if too little fluoride is consumed?
The most obvious concern with getting too little fluoride in the diet is an increased likelihood of dental caries. This has led to the widespread fluoridation of drinking water and in doing so the incidence of dental caries in those regions tends to decrease.
What happens if too much fluoride is consumed?
Fluoride seems to be very efficiently absorbed from the digestive tract regardless of the amount consumed. Even though excessive fluoride in the body is removed in the urine, humans can overwhelm this function by ingesting larger quantities of supplemental fluoride. Fluoride toxicity is called fluorosis and problems such as alterations in bones, teeth, and possibly excitable cells may result. Mottling of teeth is evidence of dental fluorosis in children. Taking gram doses of fluoride, 5 to 10 g of sodium fluoride, can lead to subsequent nausea, vomiting, and a decrease in body pH (acidosis). Furthermore, irregular heart activity and death may also result.