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A comprehensive study shows fluoride in water affects the thyroid gland. That study recommends a water filter designed to remove fluoride for those with hypothyroidism.

The addition of fluoride to drinking water is extremely controversial with some people. Dentists typically argue for it as a dental cavity preventative. I personally wonder why anyone is adding anything to my water that I did not specifically ask for.

Here is a series of 3 study summaries that discuss fluoride and its impact on the thyroid. If you want greater detail there is information about that on each link. (be sure to visit Sweetwater's blog for many more articles on this and other dangers in water: Sweetwater's Blog)


The first study concludes that fluoride in water negatively affects the thyroid gland:

The second study criticizes the first, suggesting the first study was poorly done and there is no negative effect from fluoridation. I provide the following excerpt:

‘Many non-dental health conditions have been alleged as a consequence of water fluoridation, but there is no consistent scientific evidence to support any of these putative associations. In general, the literature suggesting adverse health effects of fluoridation is characterised by poor-quality studies that do not adequately adjust for potential confounding variables.’

I personally have read this in the past; that most studies on fluoride impacts are inconclusive or poorly done. However, a third, more comprehensive, study suggests a strong correlation with hypothyroidism and levels of fluoride in water that are typically lower than the amounts added by most cities.

Fluoride from drinking water impacts on T3, T4 and TSH hormones

An excerpt from above:
‘It was found that fluoride has impacts on TSH, T3 hormones even in the standard concentration of less than 0.5 mg/L. Application of standard household water purification devices was recommended for hypothyroidism.’

The State of New Hampshire has published a document which suggests that fluoride can be absorbed through the skin. Therefore those of you who wish to avoid fluoride altogether might consider whole house fluoride removal. You may read the New Hampshire document in its entirety here.

Fluoride removal is also misleading and difficult

Many false claims are made about fluoride removal.  Fluoride is difficult to remove from water and other chemicals in the water may limit the effectiveness of any system you purchase.

You will find information on my kitchen water filters here. Here’s what you need to know:

If you wish to absolutely for certain remove fluoride from drinking water then use reverse osmosis at the sink.

My 3 stage Kitchen Defender has been shown to remove fluoride in some cities where the water quality is otherwise very good. Examples include San Francisco, Seattle, and New York City.

For those of you who do not wish to bathe in fluoride I provide whole house fluoride filters. The effectiveness are highly dependent on flow rate. That means that at low flow rates fluoride may be removed or dramatically reduced. An example is one shower. However, at higher flow rates no fluoride is removed. An example may be one shower while doing laundry or washing dishes. One must consider flow rate when buying a whole house fluoride filter.

The chemistry of your water source is also important. When in doubt follow the process I always recommend. Find your water report and see what else is in your water. If I can help please let me know.


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