Fluoride is a fairly common element in the modern world. In the United States, it has been added to the drinking water to help combat tooth decay for decades. However, scientists and doctors are trying to figure out if it has a negative effect on those suffering from chronic kidney disease or those at risk.
Kidneys filter the blood, allowing the body to create urine to expel the toxins and wastes. If the kidney is unable to do this or the capacity to do so is significantly reduced, the person is said to have chronic kidney disease.
A recent study from Sri Lanka looked at fluoride’s effect on those with chronic kidney disease. Researchers found, once a person begins to suffer from chronic kidney disease, fluoride actually begins to build in the body. When too much fluoride is in the body, a person risks fluoride toxicity.
Fluoride toxicity can begin with mild discoloring of the teeth; tiny, white flecks which disappear as the fluoride is reduced. Higher levels can cause skeletal fluorosis, where the skeleton can become less elastic and less mobile. Additionally, there is an increased risk of fractures.
Fluoride is an element that is widely distributed in the environment. The involvement of fluoride in pathogenesis of Chronic Kidney Disease of uncertain etiology (CKDu) in Sri Lanka is a much-debated topic. This study aimed to investigate the fluoride concentration in drinking water in CKDu affected areas in Sri Lanka and to evaluate the possible effect of renal impairment on serum fluoride levels in CKDu patients. Drinking water (n = 60) from the common water sources from two CKDu prevalent areas and serum samples of CKDu patients (n = 311) and healthy controls (n = 276) were collected.
Both environmental and biological samples were analyzed for the concentration of fluoride. The fluoride concentration in over 95% of drinking water samples was below the WHO guideline of 1.5 mg/L. Serum fluoride concentrations in majority of the unaffected and early-stage chronic kidney disease patients (stages 1 and 2, eGFR >60 ml/min/1.73m2) were below the normal upper concentration of 50 μg/l and significantly higher levels were observed in patients in late stages of chronic kidney disease compared to the healthy controls.
The available guidelines for drinking water are solely based on healthy populations with normal renal function. But, it is evident that once the kidney function is impaired, patients enter a vicious cycle as fluoride gradually accumulates in the body, further damaging the kidney tissue.
Thus, close monitoring of serum fluoride levels in chronic kidney disease patients and establishing health-based target guidelines for fluoride in drinking water for the kidney disease population are recommended to impede the progression to end stage renal disease.
Be sure to read some of our other articles on environmental toxins and how they impact the kidneys: