Google on FTC and Riddex and you'll see quite a few relevant links, such as http://www.ftc.gov/opa/2003/07/global.shtm That doesn't explicitly say that they don't work, but they were ordered to stop marketing the product until they can prove that the product is effective.
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Google on FTC and Riddex and you'll see quite a few relevant links, such as
http://www.ftc.gov/opa/2003/07/global.shtm
That doesn't explicitly say that they don't work, but they were ordered to stop marketing the product until they can prove that the product is effective.