Fluoride Action Network

Populations Vulnerable to Fluoride Toxicity

Fluoride Action Network | August 2012 | By Michael Connett

One of the key problems with water fluoridation is that water is for everybody, but fluoride is not. Like virtually all other drugs, a given dose of fluoride can be safe for one person but harmful to another. Indeed, a vast body of fluoride research clearly demonstrates that certain subgroups in the population are particularly susceptible to fluoride toxicity. These subgroups include:

  • infants;
  • individuals with kidney disease;
  • individuals with nutrient deficiencies;
  • communities of color; and
  • individuals with polydipsia.

Despite repeated warnings from independent scientists that these populations need to be protected from fluoride’s risks, governments imposing water fluoridation schemes have not taken any serious steps to do so.


baby receives all of its daily nutrients through breast milk, or a formula-based substitute. Breast milk, which has all the nutrients a healthy baby needs for healthy development, has extremely low levels of fluoride (about 4 parts per billion). By contrast, infant formula made with fluoridated tap water contains approximately 700 to 1,000 parts per billion of fluoride, or about 200 times more fluoride than naturally occurs in breast milk.

The historically unprecedented spike in fluoride exposure during infancy (as a result of exposure to fluoridated water in formula) has been linked to an increased future risk of dental fluorosis. As a result, many dental researchers have expressly warned that fluoridated water should not be used to make up infant formula.


Kidney disease markedly increases an individual’s susceptibility to fluoride toxicity. The kidneys are responsible for ridding the body of ingested fluoride, and thereby preventing the buildup of toxic levels of fluoride in the body. People with kidney disease (“renal insufficiency”) have a decreased capacity to excrete fluoride through their urine, and thus retain significantly more fluoride than healthy individuals. A substantial body of evidence indicates that current fluoride exposures are playing a contributing role in the development of the painful bone disease (“renal osteodystrophy”) commonly found among adults with advanced kidney disease, particularly osteomalacia. Although the risks to kidney patients have been known since before the first water fluoridation program began, governments imposing water fluoridation schemes have yet to take any steps to monitor or protect kidney patients from fluoride toxicity.


A vast amount of research, dating as far back as the 1930s, has shown that humans with nutrient deficiencies suffer toxic effects from doses of fluoride that may otherwise be safe for humans with adequate nutrition. Nutrients of particular importance to fluoride toxicity include calcium, vitamin C, vitamin D, and iodine. Further, because fluoride exerts its toxic effects through oxidative stress, many research teams have found that anti-oxidants (which includes vitamin C) provide an effective buffer to fluoride toxicity. Accordingly, populations with inadequate intakes of calcium, vitamin C, vitamin D, iodine, and anti-oxidants will be at greater risk of fluoride poisoning.


In the United States, studies dating back to the 1960s have repeatedly found that black Americans suffer higher rates of dental fluorosis than white populations. The CDC’s latest national survey confirms that this remains the case, and that a sizable percentage of black Americans now suffer from advanced forms of fluorosis, in which the teeth develop brown and black stains and the enamel softens and erodes. While it is not yet understood why this is the case, there are several possible explanations, including:

  • higher intakes of fluoride;
  • higher rates of nutrient deficiencies;
  • lower levels of anti-oxidants in their blood;
  • higher rates of chronic kidney disease; and
  • higher levels of lead in their blood (which animal research indicates could exacerbate fluoride’s toxicity.)

Based on these findings, a growing number of civil rights leaders, including Atlanta’s former Mayor, Andrew Young, and Martin Luther King’s daughter, have called for an end to water fluoridation.


Polydipsia, or excessive thirst, is a symptom caused by several diseases, including diabetes insipidus, diabetes mellitus, and some pyschiatric disorders. When a community’s water supply is fluoridated, residents with polydipsia will ingest far more fluoride than the average consumer. In fact, although fluoridation proponents claim fluoridated water cannot cause severe dental fluorosis, studies in the peer-reviewed medical literature have documented severe dental fluorosis among individuals with polydipsia drinking as little as 0.5 ppm. According to one study:

“Our patients’ daily fluid consumption while hospitalized and at home ranged from 2 1/2 to 6 times normal daily intake. They have lived in communities where the fluoride concentration is 1 ppm, the recommended amount to control caries and prevent fluorosis in children with average daily water intake. However, the patients’ excessive ingestion of water has increased the total amount of fluoride consumed to the point where they have clinical tooth mottling and laboratory evidence of fluorosis. . . . There are other pathological entities which give rise to polydipsia and polyuria. These would include central diabetes insipidus, pyschogenic water ingestion, renal medullary disease, including hypercalcemic nephropathy, hypokalemic nephropathy and anatomic and vascular disturbances and those diseases causing solute diuresis. Consumption of water in any of these disorders is excessive and could lead to fluoride toxicity in a community with acceptable fluoride concentration. Therefore, a portion of the ingested water that these children consume should be supplied from a nonfluoridated source.” SOURCE: Greenberg LW, et al. (1974). Nephrogenic diabetes insipidus with fluorosis. Pediatrics. 54(3):320-2.