Testing on effectiveness need not be double-blind because it only involves counting instances of cavities -- this is an objective measure unchanged by other information.
Fluoride is effective at preventing cavities:https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.ncbi.nlm.nih.gov/pubmed/2681730&ved=0ahUKEwiq6smagvnVAhUFNSYKHS0SBrkQFgglMAE&usg=AFQjCNGUIVSngNDDGBR2fsTGS2EOrfhE2g
Research exists that support both the idea that fluoride does and does not help cavities. Numerous specialists point to large bodies of data which show that, for example, cavities were not lowered in fluoridated areas. Whether it does or does not help, it is certainly true that water fluoridation is not a safe or ethical method of delivery.
Show me the evidence.
for what specifically?
Evidence that fluoride does not prevent cavities.
Since I do not know anything about your level of awareness of the issues involved, I will point you to an introductory video from the fluoride action network, which points to data from the world health organisation that shows that cavity levels are not lower in countries that fluoridate their water, as compared to countries that do.
It's also worth listening to this dentist who studies the topic and has a mountain of research data from the NZ specialists to backup and explain the situation:
The fluoride action network's study tracker is the most comprehensive library of studies on the topic that I know of currently and you can look through many studies in there that address this issue.
This one looked at over 100 other studies and concluded that the data was not of a high enough quality to reach a meaningful conclusion.
I am really just pulling out studies at random here..
This one showed that cavities were MORE present in fluoridated areas - probably due to fluorosis.
You have a point. I saw this article, too: https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.newsweek.com/fluoridation-may-not-prevent-cavities-huge-study-shows-348251%3Famp%3D1&ved=0ahUKEwj8153hx_rVAhXHYiYKHRu9CGoQFgh9MA4&usg=AFQjCNFsH7au0oG1Eu4tngBKIrWp7nB_-g&cf=1
Even if it were provably beneficial, it might not be ethical to force the general populace to consume it.
yes, exactly, it is the only such 'medicine' that is given in unmetered doses, period.