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Section 2: Safety
A study published in 1998349 raised concerns about the potential relationships among fluoride,
aluminum, and Alzheimer’s disease. However, several flaws in the study’s experimental design
precluded drawing any definitive conclusions.350 Concerns were noted about a number of aspects of
the protocol, including the high percentage of the test rodents dying during the study and the failure
of the researchers to account for the high levels of aluminum and fluoride in the food fed to all test
rodents.350 For decades, a small number of researchers have implicated aluminum in the development
of late-onset Alzheimer’s disease. However, the “Aluminum Hypothesis” has been abandoned by the
majority of mainstream Alzheimer’s disease scientists.351
In 2000, a study352 investigated the relationships between trace elements in drinking water and
the thought processes of 1,016 subjects over the age of 65 living in two rural areas of China.
In today’s US society, people are very mobile and tend to live in multiple places during their lifetimes.
In contrast, the rural residents of China rarely move, so in this study the researchers were able to
assume that this elderly population had used the same water and food sources throughout their
lifetimes. The researchers evaluated the effects on thought processes of seven elements (cadmium,
calcium, fluoride, iron, lead, selenium, and zinc) found in the water sources at the two study sites.
The study assessed thought processes in three areas (memory, language, and attention) using a
Chinese translation of the Community Screening Interview for Dementia. Considering the effects
of the seven trace elements, the authors concluded that fluoride was not significantly related to
impairment of thought processes such as was seen in Alzheimer’s disease.352
In a 2021 systematic review and meta-analysis of 27 studies on the association between fluoride
exposure and neurological diseases, there was no evidence to support an association between
optimally fluoridated water and any neurological disease.329
44. Does drinking water fluoridated at recommended levels cause
or contribute to heart disease?
Answer
No. Drinking water fluoridated at recommended levels is not a risk factor for heart disease.
Fact
The American Heart Association (AHA) identifies aging, male gender, heredity, cigarette and tobacco
smoke, high blood cholesterol levels, high blood pressure, physical inactivity, obesity, and diabetes
mellitus as major risk factors for cardiovascular disease.353
A number of historical studies have evaluated urban mortality in relation to fluoridation status.
National Heart, Lung, and Blood Institute of the National Institutes of Health Study
Researchers from the National Heart, Lung, and Blood Institute of the NIH examined a wide range of
data from communities that had naturally high levels, optimal levels, and low levels of fluoride in water.
The results of their analysis published in 1972354 concluded, “Thus, the evidence from comparison of the
health of fluoridating and non-fluoridating cities, from medical and pathological examination of
persons exposed to a lifetime of naturally occurring fluorides or persons with high industrial exposures,
and from broad national experience with fluoridation all consistently indicate no adverse effect on
cardiovascular health.”354
Section 2: Safety
A study published in 1998349 raised concerns about the potential relationships among fluoride,
aluminum, and Alzheimer’s disease. However, several flaws in the study’s experimental design
precluded drawing any definitive conclusions.350 Concerns were noted about a number of aspects of
the protocol, including the high percentage of the test rodents dying during the study and the failure
of the researchers to account for the high levels of aluminum and fluoride in the food fed to all test
rodents.350 For decades, a small number of researchers have implicated aluminum in the development
of late-onset Alzheimer’s disease. However, the “Aluminum Hypothesis” has been abandoned by the
majority of mainstream Alzheimer’s disease scientists.351
In 2000, a study352 investigated the relationships between trace elements in drinking water and
the thought processes of 1,016 subjects over the age of 65 living in two rural areas of China.
In today’s US society, people are very mobile and tend to live in multiple places during their lifetimes.
In contrast, the rural residents of China rarely move, so in this study the researchers were able to
assume that this elderly population had used the same water and food sources throughout their
lifetimes. The researchers evaluated the effects on thought processes of seven elements (cadmium,
calcium, fluoride, iron, lead, selenium, and zinc) found in the water sources at the two study sites.
The study assessed thought processes in three areas (memory, language, and attention) using a
Chinese translation of the Community Screening Interview for Dementia. Considering the effects
of the seven trace elements, the authors concluded that fluoride was not significantly related to
impairment of thought processes such as was seen in Alzheimer’s disease.352
In a 2021 systematic review and meta-analysis of 27 studies on the association between fluoride
exposure and neurological diseases, there was no evidence to support an association between
optimally fluoridated water and any neurological disease.329
44. Does drinking water fluoridated at recommended levels cause
or contribute to heart disease?
Answer
No. Drinking water fluoridated at recommended levels is not a risk factor for heart disease.
Fact
The American Heart Association (AHA) identifies aging, male gender, heredity, cigarette and tobacco
smoke, high blood cholesterol levels, high blood pressure, physical inactivity, obesity, and diabetes
mellitus as major risk factors for cardiovascular disease.353
A number of historical studies have evaluated urban mortality in relation to fluoridation status.
National Heart, Lung, and Blood Institute of the National Institutes of Health Study
Researchers from the National Heart, Lung, and Blood Institute of the NIH examined a wide range of
data from communities that had naturally high levels, optimal levels, and low levels of fluoride in water.
The results of their analysis published in 1972354 concluded, “Thus, the evidence from comparison of the
health of fluoridating and non-fluoridating cities, from medical and pathological examination of
persons exposed to a lifetime of naturally occurring fluorides or persons with high industrial exposures,
and from broad national experience with fluoridation all consistently indicate no adverse effect on
cardiovascular health.”354
