Can't avoid fluoride. It's in food now as well as the water.
Iodine is the only effective countermeasure but the dosage has to be as high as what the Japanese get everyday in their food.
In the US you cannot buy food with that high of a dosage as it's restricted by the FDA.
Our RDA for iodine is 150mcg or 250mcg if pregnant. The Japanese on average ingest ~80 times that amount everyday.
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