Erik Turner asked:
Hello Naked Scientists,
My wife has recently become concerned about fluoride in drinking water here in the United States. She is concerned about the long term effects of fluoride that accumulates in our bodies since fluoride is a poison. She also thinks that fluoride may have contributed to her thyroid problems since it replaces iodine.
Is there any solid science to show that fluoride in drinking water is dangerous to our health? There is a lot of information on both sides of the debate on the Internet, but I don't know who else to trust other then the Naked Scientists.
Love the show and keep up the good work,
Chris - Itís really interesting the fact that fluoride is almost universally used in many countries. Itís done because there's an understanding of the chemical reason that fluoride strengthens tooth enamel. Tooth enamel contains the chemical apatite which is a form of calcium phosphate. If you add fluoride to the diet, either in food, in salt, in drinking water, then you can add a fluoride atom to the forming calcium phosphate and you get flouro-apatite and this is much harder than just normal hydroxy-apatite Ė the normal stuff tooth enamel is made of. So you can actually strengthen your enamel significantly and that's the reason that itís done because it can give people very strong, very good quality teeth.
If you look at the levels of tooth decay that have happened since this actually was introduced, levels of tooth decay have plummeted in many places that fluoridate their water. In fact, studies have been done looking at this effect and it seems to suggest that the number needed to treat, in other words, the number of people who you have to get to drink fluoridated water in order to stop having cavities who otherwise would is about 6. So for every 6 people who drink fluoride laden water, one person will not to get cavities who would otherwise have done. So that's amazing actually. Itís a very big health impact.
But then there's a question: Are there any health disbenefits? And this is where it gets a bit murky because actually, there's very little good quality published evidence Ė one way or the other. There was a very big meta analysis that was performed by the University of York, which is probably the gold standard and has been cited by agencies and organisations all over the world since. What they actually say is they have taken 26plus studies that have looked at fluoride in water and looked at the health benefits, no cavities, and some of the disbenefits. So for instance, do people who have been drinking fluoridated water have more hip fractures for example? Because if it gets into teeth, it can also get into bones, and if itís in bones, it could potentially alter the strength and the integrity of the bone architecture. So it might make people more prone to fracture. And there's no compelling convincing evidence that it does associate more fractures. They've done a similar thing for cancers and not found any association with cancers, but the University of York team say, actually, the level of evidence is quite poor and really, we do need some very big trials and some big studies in order to look at this properly because the evidence is really quite scant.
My first inclination is to say that fluoride would have a negligible effect on the thyroid because fluoride and iodine are fairly different (despite both being halogens). I would also assume that it would pass right through the body due to the high solubility of many ionic halogen compounds.
If fluoride interfered with iodide in the thyroid then chloride would do so to a much greater extent. It doesn't so fluoride can't.
Fluoride only accumulates in bones, which I believe is the point. Madidus_Scientia, Thu, 2nd Jun 2011
The real data was around before they started adding fluoride to drink it came from areas where there is natural fluoride in the water.
Hello Naked Scientists, my friend posted a comment on facebook about thyroid function, particularly in women, being negatively affected by fluoride. She cited the following book. Please comment: http://www.amazon.com/Fluoride-Deception-Christopher-Bryson/dp/product-description/1583225269/ref=dp_proddesc_0?ie=UTF8&n=283155&s=books Lydia Jane Cypher, Sun, 14th Aug 2011
The toxicity of fluoride is well documented and if you were to read the research coming out of Europe where flouring is banned in a high number of countries you would see the horrible truth. First the fluoride is water is not the same fluoride we find in nature. The product added to our water is a waste product from pesticide and fertilizer manufacturing. Second fluoride is a highly persistent chemical which is difficult to very difficult to remove from the body. Just as you claim that it bonds to teeth and bones it also bonds very well to our cells forming cocoons around each cell. This cocoon blocks the nutrients from reaching the cell and it dies. The fluoride then moves to the next cell. Simply put, the body is starved to death over a long period of time. Ask yourself while infant toothpaste does not contain fluoride. Ask your self how a small animal will die from ingestion of a tube of tooth paste. Take it out of our water as it's so over used. Its in our water, tap and bottles, its in all soda and bear. Its in out fruits and vegetables and the animal products we eat. When do we realize this is so very wrong! Creed, Wed, 13th Mar 2013
Is this even a serious question? In 1945, "Program F" was implemented by the U.S. Atomic Energy Commission (AEC). This is the most extensive U.S. study of the health effects of fluoride, which was the key chemical component in ATOMIC BOMB PRODUCTION. One of the most toxic chemicals known to man, fluoride, it is found, causes marked adverse effects to the central nervous system but much of the information is squelched in the name of national security because of fear that lawsuits would undermine full-scale production of atomic bombs.
Many years ago, my dentist said that I was about the youngest of his patients who suffered traditional dental decay. This is because my adult teeth came through just before the water in my home city was fluoridated.
It never hurts to have large blinded studies, or perhaps re-analyze the data, especially as more and more municipalities are adding fluoride to their water. But, enough don't add fluoride, that there is always comparative data. Fluoride toothpaste?
Thousands of people are killed by water every year. Bloody dangerous stuff - ought to be banned. But there is a multinational conspiracy to take the natural product, remove all the natural organisms that live in it, make it completely tasteless and odorless, and pipe it straight into people's homes. The conspiracy is so pervasive that even wellmeaning charities have been bamboozled into supporting it and delivering this dangerous substance into primitive villages where people have lived a natural existence for thousands of years.
OK, I apologise: I should know better but...
The bit about