Flouride is a disinfectant and as such, as a topical tooth treatment works on cavities.
Although, you still end up digesting some, even if you don't swallow any toothpaste. Do you know of any other disenfectants, you'd willfully ingest? Flouride is perhaps less lethal than other disinfectants, but it isn't healthier.
Toothpaste flouride is topical flouride, yes it works to reduce cavities. Ingestion of Flouride, doesn't. Also on the subject of fluoride toothpaste, you'll notice if you read it, that there are warnings to go to a poison control center, if you ingest the stuff. All fluoridated toothpaste in the US has the warning & they don't all share the same inactive ingrediants, but they all share fluoride.
Ingestion of flouride has been linked to flourosis, cancer, kidney disease, basically as Microsofty noted. There's plenty of studies in scientific journals out there. It's scary to think about how we're slowly poisoning ourselves over the years.
I'm going to start with essentially, what I consider to be a good enough argument on its own.
1) It should be my personal choice, whether to ingest flouride. It is not ethical to force it on anyone.
2) Once in our water supply, removing it, isn't really an option and it has negative effects on the environment.
3)They dump it in the water, when they know there are proven detriments to people's health, even in low concentrations.
4)There's no control over the dose, because people drink different amounts of water.
5)They pay for this with my tax money & then I get charged again, to filter it out of my water!
More non-extreme reasons:
6) There's cheaper ways to fight cavities
7) We shouldn't have to pay for chemical compaies' waste (the fluoride)
8) Ingestion of fluoride has not been proven to reduce cavities.
--Lis, you aren't saying you drink water & never brush your teeth & therefore have never had a cavity, are you? There's lots of reasons you might not have ever had a cavity.
If you want the extreme end of things:
The first use of fluorodated water was the Nazi's flouridating the water in concentration camps for the prisoners. You really think the Nazi's cared whether the prisoners had cavities? Do a little google search on Nazi's & fluoridation, if the above reasons about civil liberties & your health don't convince you. Regardless what you else you might think about why the Nazi's did it, it is a fact that they fluoridated the concentration camp water.
I want to note, I think Nazi's used it for its capacity to kill disease causing agents in the water, as opposed to the conspiracy theory reasons.
I guess I need to make a new trip to a library, because I don't like presenting arguments without quoting the good sources to back myself up. Shame I only read about this stuff and didn't make a paper, or I'd have the list of references.
-edit-
I'm just going to link to
Greenpeace forum. They have a decent debate on the subject & links to appropriate references.
Point 1 is enough to leave me anti-drinking water fluoridation.