Fluoride toxicity is a controversial topic. Research shows it’s a neurotoxin when ingested, but it also has robust research to prove topical use of fluoride supports the remineralization of teeth and may prevent tooth decay (AKA dental caries).

To say fluoride is toxic — that you shouldn’t drink fluoridated water or use fluoride toothpaste — tends to lump you in with flat earthers and other science deniers.

But claiming fluoride is toxic is not denying science. It’s listening to what science is trying to tell us! Well-designed research is practically shouting at the medical community to stop exposing everyone (particularly children and pregnant mothers) to fluoride.

Below, we go through the history of fluoride and the science behind fluoride toxicity.

What is fluoride?

Fluoride is an inorganic ion: written as F-. Fluoride is the 13th-most abundant element in our earth’s crust. (That’s why some communities around the world drink groundwater that contains natural fluoride content.)

Fluoride is different from fluorine:

  • Fluorine with an “N” is a chemical element (F). In pure form, it is a highly toxic gas.
  • Fluoride with a “D” is the anion (F-). An anion has one more electron than proton, and thus is negatively charged.

Fluoride is used in toothpastes and drinking water to prevent cavities.

Though a point of controversy, both acute fluoride toxicity and chronic fluoride toxicity are growing problems in the United States.

The History of Fluoride: Discovery and Water Fluoridation

Fluoride’s potential for dental health was first noted in the early 1900s by dentist Frederick McKay. McKay noticed mottling on the teeth of his patients — dental fluorosis — and also found that it was associated with teeth more resistant to decay.

Upon further investigation, McKay realized the difference seemed to be attributable to the high level of natural water fluoridation in his new home of Colorado Springs. Calcium fluoride is present in groundwater at differing levels throughout the world, up to 10 ppm (parts per million) in some areas of China.

In 1937, Dr. Gerald Cox suggested dumping the fluoride in the public water supply and tout it as decay prevention. With a little evidence, including a study performed only on rats, another researcher Dr. H. Trendley Dean corroborated his claims.

With extensive lobbying, the US Public Health Service endorsed fluoridation. And still endorses it today.

Before the US would begin fluoridating the water, they wanted a town-comparison study conducted. But because the unfluoridated city saw a decrease in tooth decay at the same rate as the city with fluoridated water, the unfluoridated city was thrown out of the study.

The new version of the study — only featuring the fluoridated city — was used to justify fluoridating public drinking water. And the US has put fluoride in the water ever since.

The use of sodium fluoride was then implemented in local water supplies throughout the United States. But sodium fluoride (not the same compound as what’s naturally found in water) is not what is likely in your tap water.

Hydrofluorosilicic acid (HFA or HSA) was once known as a highly toxic waste product from the fertilizer industry, before anyone added it to toothpaste or drinking water. To sell this waste byproduct, HFA was successfully marketed as a rat poison and insecticide.

Now, the same companies who were once fined for dumping toxins into public water supplies are now paid by the federal government for a similar job. HFA accounts for about 90% of the fluoride in US drinking water.

The CDC named the addition of fluoride to public drinking water “one of 10 great public health achievements of the 20th century”.

Is fluoride toxic?

Yes, fluoride is toxic in large quantities. It is a point of controversy in the medical and scientific communities whether the level of fluoride ingestion from fluoridated drinking water and fluoridated toothpaste constitutes “large quantities”.

How much fluoride is toxic?

According to the conventional medical community, the lethal dose of fluoride for most adults is 5-10 grams of fluoride. According to the Fluoride Action Network, the lethal dose of fluoride is closer to half a gram of fluoride, for an average adult. (This breaks down to 5mg/kg of body weight.)

0.2 grams of fluoride causes abdominal discomfort.

For reference, most fluoridated water contains less than 1 milligram of fluoride per liter. That means 200 liters of fluoridated water contains enough fluoride to cause noticeable abdominal distress — not taking into consideration fluoride from other sources.

The toxicity of fluoride is a point of controversy. There are plenty of scientific studies that have observed adverse health effects from ingestion of fluoride, even trace elements.

How does fluoride affect the brain?

In children, high fluoride levels are poison to the brain. Children living in areas with fluoridated public drinking water seem to have lower IQ scores (lower by 7 points, with a standard deviation of 15). Fluoride exposure to the mother may also increase risk of ADHD or autism in infants.

In adults, the effects of fluoride poisoning are still dire. High levels of fluoride negatively impact ability to learn, memory, and general cognitive performance.

Fluoride Toxicity Symptoms

What are the symptoms of fluoride toxicity? These are the adverse effects of high levels of fluoride:

These are the adverse effects in infants whose mothers ingest a toxic amount of fluoride:

Does fluoride prevent cavities?

Yes, fluoride can prevent cavities when applied topically to the teeth. But it is toxic to humans, so Dr. George’s recommendation is to avoid it. Small amounts of fluoride in your drinking water and toothpaste build up over time — quicker than you may think.

Many healthcare practitioners promote the benefits of fluoride to dental health, blindly accepting biased research, often from non-scientific sources.

Numerous researchers have attempted to show that fluoride added to public water systems reduces tooth decay, and many of these studies are the basis for today’s fluoridation campaigns.

There has yet to be a double-blinded study (a critical requirement in eliminating examiner bias) successfully supporting this hypothesis. In fact, several epidemiological human studies have revealed results to the contrary.

Many studies suggest that fluoride makes no difference in cavity prevention. This is because fluoride works by hardening the outer layer of the tooth (enamel) instead of removing the cavity itself.

Fluoride acts by interfering with the enzymes necessary for producing intact collagen, leading to formation of imperfect collagen and irregular bone. This leads to weak, brittle enamel since fluorapatite is formed with a weak ionic bond (instead of a covalent bond).

Theoretically, fluoride may not actually strengthen teeth but work by preventing the development of teeth. In fact, fluoride can make tooth enamel weaker! Fluorosis (too much fluoride, particularly before the age of 8) causes teeth to be weak and brittle, resulting in cosmetic blemishes as well as tooth fractures.

Fluoride Toothpaste Alternatives

Hydroxyapatite is the most promising up-and-coming fluoride alternative. Our very own Dr. George suggests using a hydroxyapatite toothpaste to properly remineralize teeth and prevent tooth decay.

Our favorite toothpastes include:

  • Risewell
  • Orawellness
  • Biocidin (AKA Dentalcidin)

How to Avoid Fluoride Toxicity

Avoiding fluoride concentration is hard when you’re concerned about your oral health. But more and more companies are offering fluoride-free alternatives.

Fluoride is hidden in many oral health products:

  • Fluoride varnish
  • Crown cements
  • Dental filling materials
  • Polishing pastes
  • Most mainstream toothpastes
  • Some medications

However, there are certain dental products that do not contain fluoride and have more biocompatible ingredients. Look for these fluoride-free products:

  • Voco
  • Admira Fusion Ormocer
  • G-bond
  • SE bond

Even regular bottled water and tap water contain excess fluoride (in the US at least).

The best water filters that get rid of fluoride are:

  • Reverse osmosis filters
  • Gravity filters
  • Pitcher filters
  • Distillers

All water filters are not the same. Check out this blog on filters to find the best.

Do all countries fluoridate water?

Several world countries (especially in Europe) have banned fluoridation, while others have never fluoridated their drinking water. In fact, only 2% of the total European population lives in a fluoridated area.

These are some of the countries who have banned or do not practice fluoridation of their public drinking water:

  • Austria
  • Belgium
  • Czech Republic
  • Estonia
  • France
  • Germany
  • Greece
  • Hungary
  • Latvia
  • Netherlands
  • China
  • South Korea

In India, they have built facilities to remove excessive fluoride from water, to avoid the toxic effects of excess fluoride intake, such as skeletal fluorosis or hypocalcemia. There are natural sources of fluoride which affect community water across the world, including India.

However, public fluoridation is a major health concern here in the U.S.

Looking for a Future Free of Flouride Toxicity

Going fluoride-free is easier than it has been in 75 years!

Here at Pure Holistic Dental, we believe in fluoride-free cavity prevention. Our approach is focusing on the pH balances of the saliva, making adjustments to patient’s nutrition, and so much more.

We are proud to serve the greater Houston area. To book your appointment with us, give us a call at 713-489-3790, or click “Schedule Appointment” on any page of this website.


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