Fluoride Action Network

Study: Low-level fluoride exposure may reduce kidney and liver function in adolescents

Fluoride Action Network | Bulletin | August 9, 2019

Is Fluoridation safe?­­

For those who pay attention to the published scientific studies the answer is “no.” But for public health officials and other diehard promoters of fluoridation, the answer is “yes” – and has been for over 70 years. And it HAS to be “yes” because the moment they entertain any doubts on the matter they know the practice has to end. Even if they call for more studies to resolve any doubts it is tantamount to admitting that this practice has been, and continues to be, a huge experiment with the health of millions of people. Such experiments are not allowed.

With each new study indicating the possibility that fluoride harms tissues other than the teeth fluoridation promoters attack the study’s methodology, or the relevance to water fluoridation at 0.7 ppm, or the authors, or the journal where it is published. We have seen this dozens of times in recent years with the many studies that indicate that fluoride can damage the brain of both animals and humans.

But now these self-serving reflex reactions are becoming less convincing for U.S. officials as several studies finding harm have been funded by U.S. agencies like the National Institutes of Health and the National Institute of Environmental Health Sciences.

One such study was published in the journal Environment International yesterday, indicating that fluoride at commonly experienced doses can damage the kidneys and livers of adolescents.

The authors state, “To our knowledge, this study represents the first population-based study in the U.S. to examine the relationship between chronic low-level fluoride exposure and kidney and liver related parameters among adolescents.”

According to the Fluoride Action Network’s health database, there are over 270 published fluoride studies on the kidney and 140 studies on the liver. While it’s well known that the kidney accumulates more fluoride than any other organ in the body, less known is that a child excretes only 45 percent of fluoride in urine via the kidney compared to a healthy adult who clears it at a rate of 60 percent.

The following is a press release from Mount Sinai Hospital / Mount Sinai School of Medicine, and it puts this important new study into context.  The study was performed by researchers at the Icahn School of Medicine at Mount Sinai and funded by the U.S. Centers for Disease Control & Prevention (CDC).

Fluoride exposure may lead to a reduction in kidney and liver function among adolescents, according to a study published by Mount Sinai researchers today, August 8, in Environment International. 

The study examined the relationship between fluoride levels in drinking water and blood with kidney and liver health among adolescents participating in the National Health and Nutrition Examination Survey, a group of studies that assess health and nutritional well-being in the United States. The findings showed that exposure to fluoride may contribute to complex changes in kidney and liver function among youth in the United States, where 74 percent of public water systems add fluoride for dental health benefits. Fluoridated water is the main source of fluoride exposure in the U.S.

The findings also suggest that adolescents with poorer kidney or liver function may absorbmore fluoride in their bodies.

While fluoride exposure in animals and adults has been associated with kidney and liver toxicity, this study examined potential effects of chronic low-level exposure among youth. This is important to study because a child’s body excretes only 45 percent of fluoride in urine via the kidneys, while an adult’s body clears it at a rate of 60 percent, and the kidneys accumulate more fluoride than any other organ in the body.

The study analyzed fluoride measured in blood samples of 1,983 adolescents and the fluoride content of the tap water in the homes of 1,742 adolescents. Although the tap water fluoride concentrations were generally low, there are several mechanisms by which even low levels of fluoride exposure may contribute to kidney or liver dysfunction.

This study’s findings, combined with previous studies of childhood exposure to higher fluoride levels, show there is a dose-dependent relationship between fluoride and indicators of kidney and liver function. The findings, if confirmed in other studies, suggest it may be important to consider children’s kidney and liver function in drafting public health guidelines and recommendations.

Potential health side effects include renal system damage, liver damage, thyroid dysfunction, bone and tooth disease, and impaired protein metabolism. 

-End of press release-

Title of Study: Fluoride exposure and kidney and liver function among adolescents in theUnited States: NHANES, 2013–2016.
Authors: Malin AJ, Lesseur C, Busgang SA, Curtin P, Wright RO, Sanders AP.
Journal: Environment International
Published: August 8, 2019

The National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to assess the health and nutritional status of adults and children in the U.S. The survey is unique in that it combines interviews and physical examinations. NHANES is a major program of the National Center for Health Statistics which is part of the Centers for Disease Control and Prevention and has the responsibility for producing vital and health statistics for the Nation.

• See the
Press Coverage on this study

• See the published studies on fluoride’s effects on the Kidney and the Liver.

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