from Richard L. Shames MD & Karilee H. Shames PhD, RN

Apr 27 2006

What changed our thinking so dramatically on this important issue? While reviewing medical studies for a new book, we were shocked to learn about the disturbing fluoride-thyroid connection.

We had been a prevention-oriented doctor-nurse team working together for twenty-five years. We had raised three children together, and had always viewed good dental care as an integral part of a complete health program. After training at Harvard and Walter Reed respectively, Rich worked at the National Institutes of Health and Karilee served as a nursing professor, before we each eventually settled into private practice.

While researching influences on the thyroid gland, we were astounded by the large number of fluoride citations. We were confronted with long lists of articles, from scientists around the world, reporting in medical journals about the harmful effects of fluoride.

We then did a review of the history of thyroid treatment, which showed that fluoride had previously been used by the medical profession to deliberately slow down overactive thyroid glands. It is no longer used for that purpose, only because now there are stronger anti-thyroid drugs [like Tapazole and PTU].

This surprising data was at first an unexpected challenge to our medical and nursing education. But then we recalled being taught that no substance has just one action on the human body. They all have multiple actions. Every medicine has a good action, called “the benefit,” and other less desirable actions called “side effects.”

At this point, we felt compelled to investigate further. After reviewing hundreds of articles and books, it became clear that, regardless of any other benefits and side effects, fluoride could indeed be considered a “hormone disruptor.” These are a class of chemicals from many unrelated sources, that have the unintended consequence of altering the proper function of important hormones in the body, such as thyroid.

For example, in the Archives of Oral Biology (1982, Volume 27), Kleiner found that fluoride interfered with proper metabolism of cyclic-AMP and thus diminished cellular energy.

Next, a career university scientist showed us a large textbook about the mechanisms of fluoride tissue harm. Kenneth Kirk in his carefully written volume called Biochemistry of the Elemental Halogens and Inorganic Halides (Plenum Press NY, NY: 1991), described fluoride’s remarkable disruption of enzyme systems.

We then consulted with a toxicology expert, who explained still another harmful fluoride effect. It progressively disrupts the sensitive G-proteins. These are the building blocks of our body’s hormone receptors. (For example, receptors are where thyroid hormone actually starts doing its job at the cell level.)

But at what dilution did fluoride have this disruptive effect? At high concentrations, it is well known to be acutely poisonous and caustic. Could it be that at the low concentrations in municipal water, teeth are being helped without thyroids being harmed?

Subsequent research on fluoride/thyroid was just as worrisome. Moreover, an added problem appeared. We learned that the source of fluoride for municipalities is not sodium fluoride, the compound used by researchers to determine benefit versus risk. Instead, surprisingly, we found that what is added to almost all city water when it is fluoridated is the industrial waste product hydrofluosilicic acid.

This scrubber waste item, generally from phosphate fertilizer production, is frequently contaminated with varying amounts of cadmium, aluminum, arsenic, lead, or mercury. We found serious studies showing that minute amounts of these heavy metals (much less than would generally be considered toxic) are harmful in various ways when combined with fluoride. Moreover, we were amazed to find out that not a single safety test has ever been performed on hydrofluocilicic acid!

This larger environmental issue became the topic of our more recent book, Feeling Fat, Fuzzy, or Frazzled? (Hudson/Penquin, 2005) With fluoride added to city water, many millions of people are deliberately exposed to a hormone-altering agent. There is certainly now a massive epidemic of low thyroid, low adrenal, and low functioning sex glands. Many people rightly complain, “There must be something wrong with my hormones.”

Fluoride is, of course, just one of a great many environmental hormone disruptors. However, it is the only one we purposely put into our drinking water. Perhaps the most sensitive among us are like the canaries brought down into the mines. They might be feeling the adverse effects first. Their vague symptoms of ill health could be the early warning signal for us all.

If your levels are low, it could be that the not-so-innocent water additive is playing a role. You might be as surprised as we were. And maybe you too will change your mind about fluoride.