for letter sent to 
Prime Minister Trudeau and all Canadian Premiers
September 1st, 2021





There is an ever-growing body of peer-reviewed studies, beginning in the mid-1990s, that indicate that fluoride is neurotoxic.


To date, more than 69 human studies, most from endemic fluorosis areas in China, have associated lowered IQ with fluoride exposure.  Promoters of water fluoridation have dismissed the relevance of these studies (a) because of methodological limitations and (b) because many—but not all—of these findings occurred at higher fluoride concentrations than those used in water fluoridation programs. Nevertheless, there has been general agreement that the findings have been remarkably consistent [Choi et al., 2012].


A very significant improvement in the quality of these studies occurred in 2017, when the first of four prospective cohort studies funded by the National Institute of Environmental Health Sciences [NIEHS] in the United States were published: [Bashash et al., 2017 and 2018]; [Green et al., 2019] (also funded by Health Canada) and [Till et al., 2020].  Canadian researchers were involved in all of these rigorously designed studies.


For the first time, the studies included pregnant women and their offspring. This was important, because fluoride is known to cross the placenta. Measurements of both exposure and outcome were made at the individual level (previously these were made less precisely at the community level, in so-called “ecological” studies).


Also, the study by Till et al., 2020 showed that the infant brain is also susceptible to damage from fluoride. They showed a large reduction in IQ when children were bottle-fed as babies in communities which were fluoridated, compared with babies who were bottle-fed in non-fluoridated communities.


Most importantly, the fluoride exposures in all these studies were at levels commonly experienced by pregnant women and children in fluoridated communities in Canada. The weight of evidence now strongly suggests that fluoride is capable of damaging both the fetal and the infant brain even at very low levels.


Based upon Philippe Grandjean et al.’s Benchmark Dose Analysis, offspring born to women exposed to fluoride doses commonly experienced in communities at 0.7 ppm, would experience a loss of 4 to 5 IQ points. To put that into perspective, at the population level, a shift downward of 5 IQ points halves the number of very bright children (IQ >130) and increases by 57% the number of children needing special care (IQ <70).  Both changes have enormous social and economic ramifications for Canada.


According to Grandjean, because of the large number of children being deliberately exposed to fluoridated water, fluoride is causing a greater overall loss of IQ points today than lead, arsenic or mercury.


The loss of IQ points has lifelong consequences. For the individual, it has been estimated that a loss of one IQ point would reduce lifetime earnings by $18,000 [Grandjean et al., 2012].  For the whole Canadian population, we are talking about losses of billions of dollars in lifetime earnings.


The Fluoride Action Network in the United States has prepared a review of fluoride’s neurotoxicity from the Mother-Offspring studies, accessible here.







A major prospective cohort study from Sweden demonstrates a higher risk of hip fractures in post-menopausal women associated with long term exposure to natural fluoride at levels that are in the same range as Canadian water fluoridation rates [Helte et al., 2021]. This is a very serious finding because it is well known that hip fractures in the elderly are debilitating, costly to treat, lead to a loss of independence, institutional care and often shorten the life of those impacted.  This finding also underlines the fact that fluoride can impact our health from womb to tomb, effecting the brains of the fetus and the bones of the elderly after lifetime exposure.


Kidney and liver function, hyperuricemia and reproductive endocrinology


Recent epidemiological studies conducted in the United States, using individual biomarker measures of fluoride exposure, have found an association between low to moderate fluoride intake and impaired kidney and liver function [Malin et al., 2019], increased risk of hyperuricemia [Wei et al., 2021], as well as adverse effects on reproductive endocrinology in American adolescents [Bai et al., 2020].