Risks to Formula-Fed Infants from Fluoride in Water



In 2012, the State of New Hampshire passed a law requiring a notice on utility bills of the risk of dental fluorosis to infants fed formula mixed with water that is fluoridated. Some individual US cities have taken similar action.


In Canada, no government agencies or medical/dental associations are providing  sufficient warnings of the risk of fluorosis, or other harms, to infants who are fed exclusively using formula mixed with fluoridated water.


A 2-3 month old baby weighing 5 Kg might consume dry formula mixed with 1 litre of artificially fluoridated water every 24 hours. 1 litre contains about 700 mcg of fluoride, which works out to 140 mcg/Kg/day for a baby of this weight.


The Canadian Dental Association (Use of Fluorides in Caries Prevention-2012-Pg 4) says that infants should not consume more than 50-70 mcg/Kg/day in order to minimize the risk of Dental Fluorosis. Their endpoint in judging harm is Moderate or Severe Fluorosis. This means that the above baby is getting at least twice the dose that the CDA says puts them at risk of harm.


Those of lower income and education are more likely to bottle feed their babies from birth rather than breast-feed. Instead of getting 4-9 mcg of fluoride per day from breast milk, these already disadvantaged babies are getting 700 mcg, or more, of a substance that a Harvard researcher has said: " .... seems to fit in with lead, mercury, and other poisons that cause chemical brain drain,”.


The situation is even more risky for those drinking well water. Health Canada sets the upper limit for fluoride in drinking water at 1500 mcg/litre; a level that gives many formula-fed infants four times the dose that the CDA says puts them at the risk of fluorosis, in the critical first year of brain development.  This may not be a problem in the Peterborough area, where the groundwater is naturally low in fluoride, but levels at or above 1500 mcg/litre are not uncommon in wells elsewhere in Canada. Instead of warning new mothers, Health Canada claims that the levels of fluoride they endorse are safe for everyone.



Peterborough Public Health is also understating the problem, and misleading the public with information on their website:


 “Is it safe to feed my baby formula mixed with fluoridated municipal tap water?


Yes. Fluoridated municipal tap water is safe to prepare infant formula. Fluoride is vital for the health of teeth and bones and can help prevent cavities. Fluoridated water is a primary source of fluoride. If a child is exclusively consuming infant formula reconstituted with fluoridated water, there may be an increased chance for mild enamel fluorosis, but enamel fluorosis does not affect the health of the child or the health of the child’s teeth. The following waters are not recommended when preparing infant formula: distilled, reverse osmosis, softened, carbonated, mineral, fruit flavored bottled water. Parents and caregivers who are concerned about fluoride levels can contact their municipality to find out the level of water fluoridation in their area, talk to their dentist, doctor, or clinical registered dietitian about their concerns, use ready-to-feed formula that does not require the addition of water, or use water with lower levels of fluoride for formula preparation. If you have questions about safely preparing infant formula contact a public health nurse


This information has a number of problems. First, the claim that “Fluoride is vital for the health of teeth and bones...”, is false.  Fluoride is not an essential nutrient. No disease, including tooth decay, has ever been induced by limiting fluoride intake.  PPH also claims that only Mild Fluorosis is a risk to formula-fed infants, and that Mild Fluorosis is only a cosmetic problem.  Their first claim is not supported by the levels and endpoints used by the CDA or those used by the US Institute of Medicine. http://www.nationalacademies.org/hmd/Activities/Nutrition/SummaryDRIs/~/media/Files/Activity%20Files/Nutrition/DRIs/New%20Material/5DRI%20Values%20SummaryTables%2014.pdf


Please refer to the Tolerable Upper Intake for Elements chart. The levels listed are to minimize  “adverse health effects”.  In the US, the only level of Dental Fluorosis considered an adverse effect is Severe; not Mild or even Moderate. According to the IOM, formula-fed infants are ingesting the upper threshold dose of fluoride for risk of Severe Fluorosis.   This doesn't mean that all formula fed infants will develop Severe Fluorosis, but it  does mean that they have been over-exposed to a degree that, if it were to continue through childhood, due to the effects of swallowing toothpaste and continued ingestion of fluoridated water, would place them at high risk of Severe Fluorosis of their permanent teeth.  Even if the child's dosage levels were to drop off after infancy to the point that Severe Fluorosis doesn't occur, the amount ingested in the first year has bumped the child's risk to a higher level than would have occurred had the formula been mixed with fluoride-free water.   This is due to the cumulative nature of fluoride exposure (see research reference below) , which is accentuated by early ingestion, because infants eliminate as little as 13% of ingested fluoride compared to adults who eliminate about 50%.


With regards to the PPH claim that Mild Fluorosis is only a cosmetic problem, here is a description for what is known about the mechanism for the formation of Dental Fluorosis:


Biological mechanisms of dental fluorosis relevant to the use of fluoride supplements.


DenBesten PK1.




Fluorosis occurs when fluoride interacts with mineralizing tissues, causing alterations in the mineralization process. In dental enamel, fluorosis causes subsurface hypomineralizations or porosity, which extend toward the dentinal-enamel junction as severity increases. This subsurface porosity is most likely caused by a delay in the hydrolysis and removal of enamel proteins, particularly amelogenins, as the enamel matures. This delay could be due to the direct effect of fluoride on the ameloblasts or to an interaction of fluoride with the proteins or proteinases in the mineralizing matrix. The specific mechanisms by which fluoride causes the changes leading to enamel fluorosis are not well defined; though the early-maturation stage of enamel formation appears to be particularly sensitive to fluoride exposure. The development of fluorosis is highly dependent on the dose, duration, and timing of fluoride exposure. The risk of enamel fluorosis is lowest when exposure takes place only during the secretory stage, but highest when exposure occurs in both secretory and maturation stages. The incidence of dental fluorosis is best correlated with the total cumulative fluoride exposure to the developing dentition. Fluoride supplements can contribute to the total fluoride exposure of children, and if the total fluoride exposure to the developing teeth is excessive, fluorosis will result.

PMID: 10086925

[PubMed - indexed for MEDLINE]


Without research examining correlations between Dental Fluoroisis and systemic health effects, there is no way that anyone can say with any certainty that Mild Dental Fluorosis is only a cosmetic problem.


“...subsurface hypomineralizations or porosity” is a structural change in the tooth enamel.  Is it logical to believe that   “interaction of fluoride with the proteins or proteinases” only occurs in teeth, and not in other areas of the body, and that Dental Fluorosis is not also a marker for a  systemic effect?

Research in the area of harm to the whole body is minimal, but recent studies have suggested  associations between fluoridated areas and increased levels of ADHD:




and lower thyroid function:




Research in these areas, which should have been done before fluoridation was started, needs to be expanded. Claims of safety based on casual observation are not sufficient.


Despite endorsing the use of fluoridated water, Peterborough Public Health also provides an option to concerned parents to “...use water with lower levels of fluoride for formula preparation”.  This  is a good suggestion, but confusing, since they had just “not recommended” the two most common types of fluoride-free water, distilled and reverse osmosis, in the previous sentence.


In an attempt to bring some awareness to the infant fluoride  problem, we are offering free RO water for formula to new mothers who must formula-feed.  Please contact our office for details, or if you would like further information about fluoride.




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