Fluoride and oral health - Benefits, recommendations and controversies

Fluoride consumption is a common practice in the field of oral hygiene. However, its use is not without debate and controversy. We talk at length about fluoride in this post.

1) What is fluoride?

Fluoride is a pure chemical element, classified as a halogen on the periodic table. It is a pale yellow, highly toxic and reactive gas in its pure form. Fluorine is not found in a free state in nature due to its reactivity, but is always combined with other elements in the form of compounds, called fluorides.

1a) Is fluorine the same as fluoride?

No, fluoride refers to ions or compounds that contain fluorine. Fluoride is the form in which fluorine is generally found in the environment, for example, in water and in various minerals. In common usage, especially in contexts related to dental health or water treatment, "fluoride" often refers to the fluoride ion (F^-) or to compounds such as sodium fluoride (NaF), which is used in toothpastes and in water fluoridation. Therefore fluorine is the element in its pure state and is extremely reactive and dangerous as a free gas, while fluorides are compounds that contain the element fluorine in a safe and stable form, usually in combination with other elements. Fluoride has been used in oral health for decades due to its properties to prevent tooth decay. However, its use has also generated controversies and myths that are worth clarifying based on current scientific evidence.

2) The benefits of fluoride in our body and mouth

This element helps strengthen tooth enamel, the hard tissue that covers the teeth, making it more resistant to the attack of acids produced by bacteria in the mouth. Diverse studies have shown that fluoride can reduce demineralization and promote remineralization of areas already affected by cavities.

2a) Fluoride helps prevent tooth decay

The most notable function of fluoride is its ability to help prevent dental enamel demineralization. Fluoride is incorporated into enamel during and after its formation, making teeth more resistant to the acids produced by bacteria in dental plaque. This helps prevent the development of cavities.

 2b) Enamel remineralization

In addition to preventing demineralization, fluoride also promotes remineralization, the process by which tooth enamel repairs itself after being attacked by acids. Fluoride attracts other minerals such as calcium and phosphate to enamel, helping to repair damaged areas before they become cavities.

2c) Bactericidal effect

Fluorine has the ability to inhibit bacteria enzymes that metabolize sugars, thus reducing the amount of acid they can produce. This effect helps control the proliferation of bacteria that cause tooth decay.

2d) Fluoride also has a positive effect on bones

Fluoride can have a positive impact on bone density when considered in adequate amounts. Some studies suggest that moderate exposure to fluoride may increase bone mineral density in people, especially those who are at risk for osteoporosis. This is because fluoride can stimulate the formation of new bone tissue.

3) What happens if I don't get enough fluoride?

Fluoride is not an essential nutrient in the traditional sense, since the human body does not require it to carry out its daily vital functions as it does with other minerals such as calcium or magnesium. However, the lack of fluoride, can lead to various dental problems especially in the early stages of life:

3a) Increase in tooth decay

A lack of fluoride can significantly increase the risk of tooth decay, whether in drinking water, dental products or in the diet. This is particularly critical in children and adolescents whose teeth are developing, but it also affects adults.

3b) Weak tooth enamel

Tooth enamel is not strengthened properly without enough fluoride, which makes it more susceptible to acid attacks. This can increase the likelihood of tooth damage and wear.

3c) Economic and health costs

At the population level, a generalized fluoride deficiency could lead to an increase in dental diseases and, consequently, to higher dental health costs and a reduction in quality of life due to dental pain and tooth loss.

4) Controversies and false myths about fluoride

Despite its proven benefits, the use of fluoride is not free of controversies and false myths about which we are going to talk below.

4a) Dental Fluorosis

One of the main points of debate is dental fluorosis, a condition that occurs when too much fluoride is ingested during tooth development. Fluorosis can cause staining and, in severe cases, erosion of tooth enamel, which can affect the appearance of the teeth and require cosmetic treatment. However, it is important to note that fluorosis only occurs under conditions of excessive exposure and is very rare in places where fluoride levels are controlled.

4b) Calcification of the pineal gland

Recently, there has been debate about the possible relationship between fluoride and calcification of the pineal gland, a small organ in the brain that regulates melatonin, a hormone essential for controlling circadian rhythms, such as sleep-wake cycles, affecting patterns. sleep and other biological processes. Some studies have suggested that high levels of fluoride could be associated with higher rates of calcification in this gland [(Luke, 2001)]. However, these studies are preliminary and have not established a direct causality between fluoride exposure and adverse effects in pineal function. More research is needed to fully understand this relationship.

As to whether the use of fluoridated toothpastes increases fluoride accumulation in the pineal gland, the available studies have not directly addressed this question. Studies on the effectiveness of toothpastes with different concentrations of fluoride have focused primarily on their impact on dental health and not on the specific accumulation of fluoride in the pineal gland. It is important to note that most of the available research discusses the effects of fluoride in general, from all sources including drinking water and food, and not specifically from toothpastes. Additionally, the process of calcification and fluoride accumulation in the pineal gland seems to be more related to long-term exposures and older age.

4c) Can fluoride cause cancer or serious illnesses?

There is no scientific evidence that supports that fluoride at the doses used in water fluoridation or dental products causes cancer or any other serious disease. Studies that have evaluated these statements have not found significant correlations.

4d) Is fluoride a poison?

Another common myth is that fluoride is a “poison” and that its addition to drinking water is detrimental to overall health. This myth is based on misinterpreted studies and the toxicity of fluoride at levels much higher than what is used in oral health. Like any other chemical, it's all about using the right doses. Current scientific evidence supports that the use of fluoride in appropriate concentrations is safe and effective to prevent tooth decay.

5) Dietary sources of fluoride

Having explained the benefits and controversies of this substance, we now talk about where it is present. Various foods and water naturally contain fluoride, although quantities can vary significantly depending on geographic location and processing.

5a) Foods and drinks that provide fluoride

Although there are several products that contain it, we highlight:

• Black and green tea contains between 0.3 to 0.5 mg. per cup, depending on the duration of the infusion and the type of water used.
• Fish consumed with bones, such as sardines, can contain up to 0.2 mg. per 100 g.
• The raisins may have approximately 0.23 mg per 100 g.

These values ​​may vary and the bioavailability of fluoride from foods also depends on the food matrix and culinary processing.

5b) Drinking water contains fluoride

Fluoride content in drinking water also varies considerably:

• The water from fluoride generally contains less than 0.3 mg/L fluoride.
• The waters naturally fluoridated They can be between 0.3 and 1.0 mg/L, depending on the source.

- In many countries, fluoride is added to drinking water to reach a level of approximately 0.7 to 1.2 mg/L, optimizing the prevention of dental caries with minimization of fluorosis risks.

5c) Fluoride in dental products

Compared to dietary sources, toothpastes and other dental products contain significantly higher fluoride concentrations:

• The toothpastes for adults contain between 1000 and 1500 ppm of fluoride, which is equivalent to 1 to 1.5 mg. of fluorine per gram of pasta. Using a recommended amount of paste (approximately 1 gram), 1 to 1.5 mg would then be applied. of fluoride by brushing.
• The mouthwashes have around 250 ppm. of fluoride, which is considerably less than toothpaste, but these products are used to complement brushing, not as the sole source of fluoride.

6) Advice on fluoride consumption

By comparison, it is evident that dental products designed for oral hygiene contain a much higher concentration of fluoride than food and water. However, total fluoride exposure from dental products is controlled because they are used in small quantities and are not intended to be ingested. Instead, fluoride in food and water is ingested and absorbed by the body, contributing to the total load. This is particularly important for fluoridated water systems, where daily consumption can add significantly to total exposure, especially in areas where water naturally has high levels of this mineral. Therefore, careful management of fluoride consumption is essential, balancing dietary sources and dental products to reap the benefits of caries prevention without incurring the risk of fluorosis. Health professionals recommend following local and international guidelines and regularly consulting your dentist to customize fluoride use based on individual needs and cavity risk.

6a) What are the recommended amounts of fluoride?

Recommended daily consumption varies depending on age, sex and health conditions. It is essential to differentiate between the amount of fluoride that is necessary to obtain preventive benefits against dental cavities, the amount recommended for optimal health, and the amount that could be considered toxic. These amounts are based on "Dietary Reference Intakes" provided by various health organizations. Here are the general guidelines according to the WHO:

• Babies: 0 to 6 months, 0.01 mg/day. 7 to 12 months, 0.5 mg/day.
• Children: 1 to 3 years, 0.7 mg/day. 4 to 8 years: 1.0 mg/day.
• Older children and teenagers: 9 to 13 years: 2.0 mg/day. 14 to 18 years: 3.0 mg/day.
• Adults: Men: 4.0 mg/day. Women: 3.0 mg/day. Pregnant and lactating women: 3.0 mg/day.

These amounts include fluorine coming from all sources, such as drinking water, food, beverages and dental products.

 6b) What is the toxic amount of fluoride?

Fluoride can be toxic if consumed in excessive amounts. Acute ingestion can lead to serious symptoms, including abdominal pain, diarrhea, lethargy and in extreme cases, can be fatal. Chronic toxicity, on the other hand, can result in bone fluorosis and other bone problems after consuming water with more than 4 mg/L fluoride for many years. That said, these are the tolerable upper limits:

• Children from 1 to 8 years: 2.2 mg/day.
• Older children and adults: 10 mg/day.

7) Fluoridation of water for public consumption

Fluoridation of public drinking water is one of the most effective and economical public health measures to prevent dental caries. In fact, it is considered one of the ten greatest achievements in public health of the 20th century. The World Health Organization, along with numerous dental health organizations, support water fluoridation as a safe and effective method to prevent dental decay in communities. Here are notable examples:

7a) Water fluoridation in the United States

In the United States, water fluoridation began in 1945 in Grand Rapids, Michigan. The results showed a 60% decrease in dental caries in school children, leading to the gradual adoption of this practice in many other communities. Today, approximately 74% of the U.S. population using public water systems drinks fluoridated water, and studies continue to show that water fluoridation reduces tooth decay by 25% in children and adults.

7b) Fluoride in UK drinking water

Studies have shown that children in fluoridated areas of the UK have 15% to 40% fewer cavities than those in non-fluoridated areas. A specific study in Birmingham, a city with fluoridated water, showed significantly lower caries rates compared to Manchester, which did not have fluoridation. (Roberts et al., 2022)

8) The use of fluoride in the dentist

Fluorides for professional application can be found in the form of gel, varnish, foam or rinse and are applied by the dentist in the consultation. These have different concentrations depending on the needs of each case, but they are also more concentrated than those applied at home by the patient, so they are not needed as often as these.

8a) Application of dental fluoride in children

One of the most common questions is whether fluoride is harmful to children. However, fluoride acts as a protector against cavities and is precisely in the childhood stage when its effects are most beneficial. Depending on the risk or propensity for cavities of the child to be treated, fluoride can be applied directly in the clinic from the first or second year of age, repeating from time to time, as the dentist determines it is necessary. . It is a procedure that will not cause discomfort, since the dental professional simply spreads a fluoride gel or foam on the teeth, leaves it applied for between 2 and 4 minutes and after that time, removes it.

8b) Dental fluoride for adults

Fluoride treatments for adults should adjust to your particular needs, to their individual risk of suffering from cavities and their consumption of fluoride, mostly through water.

• In the dental clinic these treatments are usually gels that are applied with a brush that “paints” on the teeth or with a mold that fits the dentition and that is left on in the mouth for about two minutes.
• If the dentist determines, it is possible to apply dental fluoride gel directly at home, since it can be purchased with a prescription depending on the needs of each adult patient and their risk of suffering from cavities.

8c) Conclusion

In summary, fluoride remains an essential tool in the prevention of dental cavities and is supported by scientific evidence such as a safe and effective component in oral health. Despite controversies and myths, the benefits of its proper use are well recognized in the medical and dental community. It is crucial to follow the recommendations of health professionals to maximize its benefits and minimize risks.