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.
Nothing on this path shook our faith in fluoride. In fact, it was not until we were working with a New York publisher that we really did our homework on this subject. The topic of our book, Thyroid Power (HarperCollins 2001), was the unexplained skyrocketing of thyroid disease and its spin-off epidemics of fatigue, depression, anxiety, infertility, and overweight.
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.
In hindsight, it did seem odd that fluoridated water was the only substance ever discovered that had a great benefit with no side effects at all. Once we thought about it carefully, it also seemed curious that fluoride was the only medicine ever to be added to public drinking waters.
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 fluorides 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 bodys 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?
No, the data showed otherwise. Contradicting the hoped-for scenario is research going back half a century. For instance, we came across a 1958 study by Galletti and Joyet, published in the prestigious Journal of Clinical Endocrinology and Metabolism. The paper was titled, Effect of Fluorine on Thyroidal Iodine Metabolism and Hyperthyroidism. These scientists showed that fluoride in the range of 2-5 mg. per day (what people now ingest in a fluoridated area) was enough to slow down thyroid function.