Fluoride was added to public drinking water 80 years ago with the belief that it prevents tooth decay; back then, little was known about its harmful impact on our health. Modern studies have demonstrated that, on top of its limited caries-preventive effect (individuals exposed to fluoride in drinking water only showed a 15% reduction in caries compared to those not exposed), fluoride impairs bone and tooth mineralization, interferes with the function of the thyroid gland, causes neurotoxicity and cognitive impairment, and is linked to lower IQ and learning disabilities in children. A well-documented effect of fluoride on bone and tooth formation is fluorosis.

Fluoride and bone health

Exposure to fluoride can compromise bone structure by impairing both bone formation and mineralization:

  • Fluoride obstructs normal bone mineralization by replacing calcium, forming fluorapatite instead of hydroxyapatite, which is weaker and more fragile, leading to bones that are prone to fractures, deformities, joint pain, and osteoporosis.
  • Fluoride inhibits key enzymes that are normally involved in bone formation, including: Ascorbate oxidase is the enzyme the body uses to regulate the levels of ascorbic acid or vitamin C. Without ascorbate, collagen, an essential component in bone formation, can’t be synthesized. Fluoride decreases the activity of this enzyme. Lysyl oxidase is an enzyme responsible for collagen crosslinking (a process that is central for the structural integrity of bone); fluoride has been shown to inhibit that enzyme, which results in the production of weaker collagen and, therefore, weaker bone. Alkaline phosphatase and acid phosphatase are enzymes that modify bone proteins and are involved in bone resorption and formation; fluoride inhibits these enzymes, leading to ineffective bone recycling. Fluoride inhibits multiple bone proteases, disrupting the balance between bone formation and resorption. Fluoride impairs the function of cytochrome c oxidase, a key mitochondrial enzyme involved in energy production. Additionally, inhibition of this enzyme exposes the cells to more oxidative damage.
  • Fluoride is genotoxic to bone; it inhibits expression of genes that regulate bone mineralization. Fluoride also affects cell signaling pathways and protein functions necessary for bone formation.

The combination of these effects of fluoride leads to dental and skeletal fluorosis, but that is not the only negative impact fluoride has on our health.

The full health impact of fluoride toxicity

In addition to its effects on bone, fluoride impairs the function of numerous systems:

  1. Neurotoxicity: Fluoride causes mitochondrial damage, neuroinflammation, and altered levels of neurotransmitters. These effects impair brain function and development, leading to cognitive impairment, decreased intelligence, mood disorders like anxiety and depression, and neurobehavioral disorders like ADHD.
  2. Reproductive toxicity: Fluoride was found to damage the ovaries and oocytes, leading to decreased female fertility in animal models.
  3. Cardiovascular toxicity: Fluoride disrupts electrolyte levels and causes low calcium and magnesium; this can cause arrhythmias. In addition, fluoride is linked to hypertension and atherosclerosis.
  4. Thyroid toxicity: Fluoride interferes with the process of iodination during the production of thyroid hormone and can cause both increased or decreased secretion of thyroid hormone.

Beyond that, fluoride toxicity causes nausea, vomiting, diarrhea, eye irritation, and skin rashes.

Tips to limit your exposure to fluoride

  1. Use a water filter that removes fluoride, especially if you live in an area with naturally fluoridated groundwater.
  2. Choose fluoride-free dental products like nHA-based toothpaste and fluoride-free mouthwash.
  3. Discuss fluoride-free dental treatments with your dentist.
  4. Be careful with foods and beverages that have a high fluoride content, like tea, seafood, and canned food.
  5. Other sources of fluoride are non-stick cookware, which releases fluoride when overheated, and some agricultural chemicals like pesticides and fertilizers contain fluoride, so wash your fruits and vegetables thoroughly and eat organic when possible.
  6. Protect your children, as fluoride is especially dangerous during brain development.

Fluoride may have some merits in certain circumstances, but adding it to drinking water is definitely not worth it. There is no justification for using it this way, as it offers no advantages when administered systemically, and even the benefits that arise from its topical use can be obtained from safer and more natural alternatives. Stay informed and make conscious choices; your health is your biggest asset.

References

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