The Truth About Fluoride: Nature's Cavity Fighter and the Myths That Surround It

Fluoride has been debated for decades, often clouded by myths and misconceptions that overshadow its proven benefits. This naturally occurring mineral has been pivotal in public health, particularly in preventing tooth decay. In this blog post, we'll explore fluoride's natural origins and its historical significance, debunk prevalent conspiracies, and try to provide an honest breakdown of studies assessing its impact on neurodevelopment and cognition.

Fluoride is a natural mineral!

Fluoride isn't a synthetic chemical concocted in laboratories; it's a mineral found naturally in water sources worldwide and in various foods and soils. For instance, the inhabitants of ancient Pompeii had fluoride in their water supply, contributing to their dental health long before modern dentistry existed (1). Archaeological studies suggest that the natural fluoride content in Pompeii's water helped reduce cavities among its citizens.

Some foods contain naturally high fluoride levels, often comparable to or even exceeding those found in fluoridated water (typically around 0.7 parts per million, or ppm). For example, brewed black tea can have fluoride concentrations ranging from 1 to 6 ppm, depending on the type and brewing time, making a single cup potentially richer in fluoride than a liter of fluoridated water. Seafood, such as sardines, can contain up to 2.5 ppm of fluoride, as marine life tends to accumulate minerals from ocean water. Similarly, raisins may contain around 0.5–2.3 ppm of fluoride due to irrigation practices and naturally high fluoride levels in some regions.

Recognizing fluoride’s natural presence and its positive impact on dental health led to the addition of fluoride to public water supplies, a measure now considered one of the greatest public health achievements of the 20th century. Since its introduction, communities have significantly reduced dental cavities among children and adults. The Centers for Disease Control and Prevention (CDC) reports that water fluoridation can reduce tooth decay by about 25% over a person's lifetime (2).

While we won't get too detailed about the mechanisms, it's essential to note that fluoride strengthens tooth enamel, making it more resistant to acid attacks from plaque bacteria and sugars in the mouth (3). This simple addition to drinking water ensures equitable access to dental health benefits, regardless of socioeconomic status. Dr. Andrea Love has a really great article on her blog that explains in way more depth how this works!

Addressing Some Conspiracies

Despite overwhelming scientific support, fluoride has been the subject of numerous conspiracy theories. Some claim it's a government ploy for mass mind control or a dangerous industrial byproduct. These theories often stem from misinformation and a lack of understanding of the science involved.

Myth 1: Fluoride Is a Toxic Industrial Waste

One concern is that fluoride used in water fluoridation can originate from industrial byproducts, such as phosphate fertilizer production. Some fluoride additives are indeed derived from industrial processes. However, these additives are purified and must meet strict safety standards set by agencies like the American Water Works Association and NSF International (5). The fluoride added to water supplies is in the form of fluoride salts, which are highly soluble and safe at recommended levels.

Acknowledging that the source can be industrial helps us understand the importance of regulation and quality control. The end product is a safe and effective means of improving dental health, not a hazardous waste being dumped into water supplies.

Myth 2: Fluoridated Water Lowers IQ and Affects Neurodevelopment

This claim is primarily based on studies conducted in areas with extremely high natural fluoride levels, far exceeding those used in public water fluoridation. A comprehensive review by the National Academies of Sciences found no consistent evidence linking fluoride at optimal levels in drinking water to adverse neurodevelopmental outcomes (4).

Let's address the elephant in the room: the individual studies examining fluoride's impact on the brain. Some research suggests potential risks, but context is crucial. For another perspective on the limitations of some of the present studies, check out this article by the Harvard School of Public Health.

Recent Studies and Their Limitations

Many studies indicate that the negative effects involve fluoride concentrations much higher than the recommended 0.7 parts per million (ppm) in drinking water. For instance, certain regions in China and India have natural fluoride levels exceeding 4 ppm, leading to health issues (6).

Bashash et al., 2017: A study conducted in Mexico suggested a correlation between higher prenatal fluoride exposure and lower IQ scores in children (7). However, fluoride levels in this study were higher than those in fluoridated water in the U.S., and the study did not account for other environmental factors like lead exposure.

Green et al., 2019: This Canadian study reported an association between maternal fluoride exposure and reduced IQ in boys but not girls (8). Critics pointed out limitations such as using urine fluoride levels (which can vary widely) and potential confounding factors.

Till et al., 2020: Examined the impact of fluoride exposure on children's IQ and found a weak association (9). However, the study's design couldn't establish causation, and the fluoride levels studied were higher than typical community water fluoridation levels.

Comprehensive Reviews

National Toxicology Program (NTP), 2020: Conducted a systematic review and concluded that fluoride is "presumed to be a cognitive neurodevelopmental hazard to humans" at high exposures (10). However, they noted that the evidence is inconsistent at exposure levels relevant to U.S. water fluoridation.

European Food Safety Authority (EFSA), 2013: Found no clear evidence of neurotoxicity at fluoride levels used in community water fluoridation (11).

Public Health England, 2018: Reviewed the effects of water fluoridation and found no convincing evidence of adverse health effects (12).

Comparing Consumption Levels

Optimal Fluoridation Level: 0.7 ppm (U.S. standard)

Levels in Studies Showing Harm: Often >2 ppm, sometimes up to 10 ppm

An average person drinking fluoridated water consumes fluoride well within the safe limits established by health authorities.

Conclusion: Embracing Science Over Myths

Fluoride remains a safe, natural, and effective tool in promoting dental health. The myths and conspiracies lack scientific backing, especially when scrutinized against the vast body of research supporting fluoride's benefits. By focusing on evidence and understanding the science, we can appreciate the role fluoride plays in enhancing public health.

References

(1) "Fluoride: A Natural Substance That Prevents Cavities," Immunologic, 2023. https://news.immunologic.org/p/fluoride-a-natural-substance-that

(2) Centers for Disease Control and Prevention. "Community Water Fluoridation." https://www.cdc.gov/fluoridation/index.html

(3) ten Cate, J.M., "Contemporary Perspective on the Use of Fluoride Products in Caries Prevention," British Dental Journal, 2013.

(4) National Academies of Sciences, Engineering, and Medicine. "Review of EPA's 2010 Draft Fluoride in Drinking Water," 2022.

(5) "Is Fluoride in Drinking Water Safe?" TIME, 2023. https://time.com/7172655/is-fluoride-in-drinking-water-safe/

(6) Chouhan, S., and Flora, S.J.S., "Arsenic and Fluoride: Two Major Groundwater Pollutants," Indian Journal of Experimental Biology, 2010.

(7) Bashash, M., et al. "Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6–12 Years of Age in Mexico." Environmental Health Perspectives, 2017.

(8) Green, R., et al. "Association Between Maternal Fluoride Exposure During Pregnancy and IQ Scores in Offspring in Canada." JAMA Pediatrics, 2019.

(9) Till, C., et al. "Fluoride Exposure from Infant Formula and Child IQ in a Canadian Birth Cohort." Environment International, 2020.

(10) National Toxicology Program. "Draft NTP Monograph on the Systematic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects," 2020.

(11) European Food Safety Authority. "Scientific Opinion on Dietary Reference Values for Fluoride," EFSA Journal, 2013.

(12) Public Health England. "Water Fluoridation: Health Monitoring Report for England 2018," 2018.