Functions: Studies show that fluoride helps strengthen the crystalline structure of bones and teeth. The calcium fluoride salt forms a fluorapatite matrix, which is stronger and less soluble than other calcium salts and therefore is not as easily reabsorbed into circulation to supply calcium needs. In teeth, this fluoride salt reduces the potential for breakdown from acids in the mouth or from demineralization, minimizing tooth decay. In bones, fluoride reduces loss of calcium and thereby may reduce osteoporosis. No other functions of fluoride are presently known, though it has been suggested to have a role in growth, in iron absorption, and in the production of red blood cells. This needs further research.

Uses: Fluoride's main use is as an additive to drinking water as well as toothpaste and mouthwash for the prevention of tooth decay. When added to water at 1 ppm, it can reduce dental caries by 30-50 percent. Fluoridated water works best, however, when its use is begun in infancy or early childhood and continued throughout childhood. Fluoride-treated water does not decrease the gum disease that may also result from poor nutrition and poor hygiene. As is typical of Western medical thinking, we treat the result as if it were the problem itself, rather than correcting the cause-the overuse of sugar and poor dietary habits in general-which may be causing decay even deeper in the body, a process that may take us many more years to discover. I wonder what new xenon-coated bandage will be invented to patch that up.

On a more positive note, the use of sodium fluoride has been shown to be helpful in the treatment and possibly the prevention of osteoporosis, though the results from various studies are mixed. Epidemiologically, the incidence of osteoporosis is slightly reduced in fluoridated-water users. In older studies, bone density, as well as blood pressure, was improved by treatment with 50 mg. of sodium fluoride (NaF) and 900 mg. of calcium daily and 50,000 IUs of vitamin D twice weekly. There is concern, however, that fluoride-treated bones will not give up calcium easily to the body when needed, which may contribute to calcium deficiency. It is obviously much better to prevent osteoporosis by eating calcium-rich foods; supplementing calcium, magnesium, and vitamin D; maintaining overall mineral balance; eating a healthy diet; and exercising regularly.

There is some preliminary research evidence that fluoride may help in treating otosclerosis, a loss of hearing due to deposits in the ear. Hearing loss in later years, when it is due to osteoporosis, or loss of minerals from the tiny ear bones, may be reduced with fluoride treatment as well.

Fluoride is not generally used as a supplement in multivitamin/mineral formulas. It is added to some infants' and young children's vitamins to aid in the prevention of tooth decay. As sodium fluoride, it is occasionally prescribed medically in the prevention or treatment of dental disease.

Deficiency and toxicity: Toxicity from fluoride is definitely a potential problem. As stated, fluoridated water must be closely monitored to keep the concentration at about 1 ppm to effectively reduce dental decay without producing side effects. At concentrations greater than 2 ppm, fluoride can cause mottling, discoloration, and pitting of the teeth, though it will still maintain tooth strength and prevent cavities. At 8 to about 20 ppm, initial tissue sclerosis will occur, especially in the bones and joints, which can cause arthritic symptoms. At over 20 ppm, much damage can occur, including decreased growth and cellular changes, especially in the metabolically active organs such as the liver, kidneys, adrenal glands, and reproductive organs. More than 50 ppm of fluoride intake can be fatal. In terms of total fluoride intake, around 20 mg. per day will usually cause some tooth discoloration and bone problems. Animals eating extra fluoride in grains, vegetables, or in water have been shown to have tooth and bone lesions. Fat and carbohydrate metabolism has also been affected. There are many other concerns about fluoride toxicity, including bone malformations and cancer.