7. Fluoride is added to the water to cause disease.
Percentage of Americans: 9%
Who believes it: N/A
When fluoridation became an official policy by Public Health Service in 1951, it wasn't long until conspiracies started spreading stating that the government was putting fluoride in the drinking water to do more than just prevent tooth decay. While it has been scientifically proven that fluoride, in small amounts, can actually be beneficial to oral health, skeptics believe that the government has been trying to use this fluoridation tactic to protect against overpopulation.