There are few things that can calm the paranoid faster than talking about fluoride in drinking water. But a new study on Friday cautiously suggests that even low fluoride levels in teens may be linked to changes in kidney and liver function. It is not yet clear whether these changes actually affect the health of teenagers, or whether fluoride is actually the main culprit.
In the 1950s and 1960s, US states and cities began adding fluoride to drinking water supplies, after decades of studies and anecdotal reports showing that fluoride can prevent caries, especially children. Today, nearly two-thirds of Americans drink fluoridated water while other countries adopt such policies.
Editor's note: Australia similarly introduced fluoride into its drinking water in the 1
There has long been a small contingent of fluoride skeptics. Their allegations largely depend on allegations of governmental action and communist indoctrination. But some scientists also argue that fluoridation, as it exists today, can have unwanted, detrimental health effects.
For example, we know that very high levels of fluoride (higher than you will ever find in fluorinated tap water) can cause neurological problems in adults. Some studies have also linked low levels of fluoride exposure to cognitive problems in the development of young animals, while several studies of the human population have found a link between fluoride exposure and lower rates of intelligence in children. But these studies largely focus on people living in China, where fluoride is naturally found in groundwater at sometimes very high levels.
The authors of this study, published at Environmental International, instead looked at more than 3,000 teenagers in America.
They used data from a nationally representative and governmental annual survey of Americans, including some people who also gave blood samples. With these samples, the team was able to track the levels of fluoride, as well as markers of kidney and liver health, in the blood of these teens. They focused on the kidneys and liver because these two organs are most exposed to fluoride when it is absorbed by the body. And all possible effects can be magnified in teens as they are less able than adults to quickly filter fluoride through their urine.
"What we said in a nutshell is that higher levels of fluoride in the blood are associated with indicators of poor kidney and liver function," lead author Ashley J. Malin, PhD, Department of Environmental Medicine and Public
The results of the study show that current levels of fluoride exposure can lead to a decrease in kidney and liver function in at least some teenagers. hi and now, even small reductions in kidney function can increase the risk of kidney disease later in life. At the same time, Malin added, it's too early to say anything definitive.
"So at this point, we do not fully know the clinical implications of these small changes, "she said." We really need more research to fully understand these consequences. "
An ideal study in the future, Malin said, will look at and compare similar groups of young people exposed to different levels of fluoridated water from a very early age age and track their health over time.
One question that may be answered by more studies is the exact direction of the fluorine bond. It may not be that chronic exposure to low-level fluorides results in poorer renal function, but people with pre-existing poor renal function are less able to metabolize fluoride, so more of it ends up in their blood. This can still be bad, since the more fluoride builds up in our bodies, the greater the potential health risks, but it would be a different problem to solve.
Malin and her team do not say that their findings should lead to changes in fluoridating policy. But she believes it is important for public health experts to explore more of these possible relationships and, if necessary, re-evaluate the consensus on fluoridation.
A reassessment of fluoride policies would not be the first for the US government in recent years. In 2015, the Ministry of Health and Human Services recommended that the optimum fluoride level in drinking water should be 0.7 milligrams per liter of water, not the range of 0.7 milligrams to 1.2 milligrams previously approved.
At this level, the agency concluded, you will still prevent the appearance of cavities while reducing the risk of dental fluorosis, a condition that causes teeth to become brown, discolored or even damaged in children over-exposed to fluoride.
“I believe that politicians should continue to consider the research ahead of them so that they can make the best decision for all possible. And I hope my research helps them, "she said.
Of course, preventing dental caries is much more than cosmetics – poor oral health is associated with a number of problems throughout the body, including heart disease, arthritis, and even dementia.
So while there is no convincing evidence that fluoride in drinking water causes harm, the weight of the evidence falls on it being a benefit to public health.