Excerpts: a new study out Thursday cautiously suggests that even low levels of fluoride in teens could be linked to changes in their kidney and liver function.
The authors of this current study, published in Environment International, instead looked at more than 3,000 teens in the U.S. They used data from a nationally representative and government-run annual survey of Americans, including some people who also gave blood samples. With these samples, the team was able to track levels of fluoride, as well as markers of kidney and liver health, in the blood of these teens. They focused on the kidney and liver because these two organs are the most exposed to fluoride when it’s absorbed by the body. And any possible effects might be amplified in teens, since they’re less able than adults to quickly filter out fluoride through their urine.
“What we found, in a nutshell, is that higher levels of fluoride in blood were associated with indicators of poor kidney and liver function,” lead author Ashley J. Malin, a postdoctoral fellow in the Department of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai, told Gizmodo by phone.
The study’s findings suggest that current levels of fluoride exposure in the U.S. can lead to reductions in kidney and liver function in at least some teens. And while the teens seemed to be healthy now, even small reductions in kidney function could increase their risk for kidney disease later in life. At the same time, Malin added, it’s too early to say anything conclusive.
“So, at this point, we don’t fully know what the clinical implications are of these small changes,” she said. “We really need more research to fully understand these implications.”
One question that more research could answer is the exact direction of the fluoride link. Maybe it’s not that chronic low-level fluoride exposure leads to poorer kidney function, but that people with preexisting poor kidney function are less able to metabolize fluoride, so more of it ends up in their blood. That could still be bad, since the more fluoride accumulates in our bodies, the greater the potential health risks, but it would be a different problem to solve.
Malin and her team aren’t saying their findings should lead to changes in fluorination policy. But she does think it’s important for public health experts to look more into these possible connections and, if needed, to reevaluate the consensus around fluoridation.