Study funded by the US Government’s NIH and NIEHS (8th August 2019) indicates that fluoride at commonly experienced doses can damage the kidneys and livers of adolescents. The study, “Fluoride Exposure and Kidney and Liver Function Among Adolescents in the United States: NHANES, 2013-2016,” was published by Environment International.

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 absorb more 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. 

See Press Coverage of this study.

15th April 2008 US National Kidney Foundation withdraws support for fluoridation, fearing lawsuit.

The US National Kidney Foundation (NKF) has issued a new position paper formally cancelling NKF’s previous position paper on water fluoridation, concluding that individuals with chronic kidney disease should be notified of the potential risk from exposure to fluorides. The document, issued on 15 April 2008, acknowledges gaping holes in research concerning kidney impacts from fluorides. The NKF has withdrawn its support for water fluoridation, and the American Dental Association has removed it from its list of supporting organisations.

This change in position follows a lawyer’s letter sent to the NKF by US attorney Robert Reeves on 18 September 2007, at the instigation of the Lillie Center Inc, a private health training company. The letter contained the following opening sentence.

“This letter is to make you aware of a window of opportunity for the National Kidney Foundation (NKF) to act on behalf of its constituents in accordance with the organization’s stated mission. Your actions or inaction in response to this letter have the potential to help or harm many patients with kidney disease, and you should be aware that NKF’s response to this benchmark notification may determine whether NKF and responsible individuals, which might include past and present Officers, Board Members and/or employees are named as defendants in anticipated legal actions now in development.”

Reeves’ letter cites the authoritative report from the National Research Council issued in 2006 that concluded that, “Early water fluoridation studies did not carefully assess changes in renal function.” The NRC report also identifies kidney patients as a “susceptible subpopulation” that is particularly vulnerable to harm from fluorides.

“The letter to the National Kidney Foundation is only the tip of the iceberg,” says Daniel Stockin of the Lillie Center. “The kidney and diabetes lawsuits are about to begin. Employers, water agencies, food and beverage sellers and manufacturers, you name it – I would suggest they immediately halt use or sale of fluoridated water or products containing it.”

The NKF has issued no press release about the April statement and has offered no direct link to the new information on its web site except when a search for the term “fluoride” is entered.

It should be noted that the NKF is funded by the US Government agency, the Centers for Disease Control and Prevention (CDC), one of the two leading promoters of fluoridation in the US, which perhaps explains its reticence in issuing appropriate warnings. The CDC itself is potentially facing ethics charges over its failure to appropriately notify the public of the NRC’s findings, especially those subpopulations identified by the NRC as being at particular risk from fluoride.

New Zealanders should be careful not to be misled by Government statements that some parts of the USA have much higher fluoride levels in the water than NZ. Fluoridated US cities have the same level as fluoridated NZ communities – 0.7 to 1 ppm, the NRC report makes it clear that the threat to kidney sufferers is at all levels of exposure, and total intake is estimated at similar levels (3 – 4 mg/day in NZ; 3 – 6 mg/day in the USA).