One problem in determining fluoride's potential harm, if any, is that it's not clear how much we get from other sources. Virtually all foods contain at least a trace: Fluoride is a component of soil, so it turns up in fruit, vegetables, and grains. But how much there is depends on where a crop was grown, because the fluoride content of soil varies from one region to another. Agricultural pesticides and irrigation water often contain fluoride, too, which is incorporated into plants. Water given to chickens, cattle, and other farm animals may also be fluoridated.
According to the CDC, the typical American gets 1 to 3 mg of fluoride per day, though experts say that is a very rough estimate. "There's a huge variation in levels of intake," says Levy. He leads a team that has been studying the diets of about 700 children in Iowa (roughly 70% of them in fluoridated communities) to get a more accurate picture of consumption of fluoride in this country. His research has already yielded some worrisome findings: About one-quarter of the children are swallowing twice as much fluoride each day as they should be.
t takes a lot of fluoride to begin developing skeletal fluorosis--at least 10 mg a day for 10 years. But endocrinologist Michael P. Whyte, MD, of the Washington University School of Medicine, the lead author of the report, says a person can get into the danger zone without quaffing gallons of tea every day. Whyte and his colleagues analyzed 10 types of instant tea for fluoride content. They found a range: Two brands contained only about 1 mg/L--Lipton Instant Diet Iced Tea Mix (Decaffeinated Lemon) and Schnucks Instant. However, most of the teas had at least twice that amount of fluoride, and one popular brand, Lipton Instant, had 6.5 mg/L. (Likewise, brewed tea can contain anywhere from 1 to 6 mg/L of fluoride, depending on the variety used, the water, and the brewing time.)
Picture a lifelong iced tea lover who guzzles a liter (about 1 quart) of a high-fluoride brand made with fluoridated water every day. Whyte suspects the scenario may not be so unusual in hot climates. "That's 7.5 mg. That's getting close to 10 mg a day," he says. "That could start to be associated with symptoms of skeletal fluorosis."
I had no idea that you could get fluoride from fruits and veggies ... and ... especially from brewed tea....
Earl Grey, hot, pass the flouride.
