Fluoride overconsumption may weaken bones and cause osteoporosis
Fluoride - which is added to water to reduce tooth decay - accumulates in and can weaken bones. To prevent bone damage or skeletal fluorosis, in 1986 the Environmental Protection Agency set 4 milligrams per liter (mg/L) as water fluoride's maximum-contaminant-level. In 2006, the National Research Council reported that 4 mg/L is too high to protect health. Yet, some brewed teas contain almost twice that concentration.
This case describes a 53-year-old British woman with a broken bone in her foot, abnormally dense bones and badly decayed teeth.
"A striking feature of our case was the very high serum, urine, nail and bone fluoride levels, to our knowledge the highest ever reported in a patient with [skeletal] fluorosis," the research team writes.
Her breakfast tea measured 7.6 mg/L fluoride, which she drank six 8-ounce-cups of daily. She also brushed her teeth 8 to 10 times a day. Adding two to three mg of fluoride from other dietary sources, this woman ingested "a chronic daily dose of 17 to 18 mg, an amount sufficient to cause the skeletal changes...," the researchers report.