Fluoride is found naturally in soil, water, and foods. It is also produced synthetically for use in drinking water, toothpaste, mouthwashes and various chemical products.
Water authorities add fluoride to the municipal water supply, because studies have shown that adding it in areas where fluoride levels in the water are low can reduce the prevalence of tooth decay in the local population.
Tooth decay is one of the most common health problems affecting children. Many people worldwide cannot afford the cost of regular dental checks, so adding fluoride can offer savings and benefits to those who need them.
However, concerns have arisen regarding fluoride’s effect on health, including problems with bones, teeth, and neurological development.
Fast facts about fluoride
Fluoride comes from fluroine, which is a common, natural, and abundant element.
Adding fluoride to the water supply reduces the incidence of tooth decay.
Fluoride protects teeth from decay by demineralization and remineralization.
Too much fluoride can lead to dental fluorosis or skeletal fluorosis, which can damage bones and joints.
Excessive exposure to fluoride has been linked to a number of health issues.
A fluoride content of 0.7 ppm is now considered best for dental health. A concentration that is above 4.0 ppm could be hazardous.
Exposure to high concentrations of fluoride during childhood, when teeth are developing, can result in mild dental fluorosis. There will be tiny white streaks or specks in the enamel of the tooth.
This does not affect the health of the teeth, but the discoloration may be noticeable.
Breastfeeding infants or making up formula milk with fluoride-free water can help protect small children from fluorosis.
Children below the age of 6 years should not use a mouthwash that contains fluoride. Children should be supervised when brushing their teeth to ensure they do not swallow toothpaste.
Excess exposure to fluoride can lead to a bone disease known as skeletal fluorosis. Over many years, this can result in pain and damage to bones and joints.
The bones may become hardened and less elastic, increasing the risk of fractures. If the bones thicken and bone tissue accumulates, this can contribute to impaired joint mobility.
In some cases, excess fluoride can damage the parathyroid gland. This can result in hyperparathyroidism, which involves uncontrolled secretion of parathyroid hormones.
This can result in a depletion of calcium in bone structures and higher-than-normal concentrations of calcium in the blood.
Lower calcium concentrations in bones make them more susceptible to fractures.
In 2017, a report was published suggesting that exposure to fluoride before birth could lead to poorer cognitive outcomes in the future.
The researchers measured fluoride levels in 299 women during pregnancy and in their children between the ages of 6 and 12 years. They tested cognitive ability at the ages of 4 years and between 6 and 12 years. Higher levels of fluoride were associated with lower scores on IQ tests.
In 2014, fluoride was documented as a neurotoxin that could be hazardous to child development, along with 10 other industrial chemicals, including lead, arsenic, toluene, and methylmercury.
High fluoride levels in pregnancy may lower offspring IQ
Find out more about how fluoride may affect cognitive development
Other health problems
According to the International Association of Oral Medicine and Toxicology (IAOMT), an organization that campaigns against the use of added fluoride, it may also contribute to the following health problems:
acne and other skin problems
cardiovascular problems, including arteriosclerosis and arterial calcification, high blood pressure, myocardial damage, cardiac insufficiency, and heart failure
reproductive issues, such as lower fertility and early puberty in girls
conditions affecting the joints and bones, such as osteoarthritis, bone cancer, and temporomandibular joint disorder (TMJ)
neurological problems, possibly leading to ADHD
One review describes fluoride as an “extreme electron scavenger” with an “insatiable appetite for calcium.” The researchers call for the balance of risks and benefits to be reconsidered.
Acute, high-level exposure to fluoride can lead to:
nausea and vomiting
seizures and muscle spasms
This will not result from drinking tap water. It is only likely to happen in cases of accidental contamination of drinking water, due, for example to an industrial fire or explosion.
It is worth remembering that many substances are harmful in large quantities but helpful in small amounts.
Flouride exists in many water supplies, and it is added to drinking water in many countries.
Fluoride is added to many dental products.
It is also used in the following dental products:
cements and fillings
gels and mouthwashes
some brands of floss
fluoride supplements, recommended in areas where water is not fluoridated
Non-dental sources of flouride include:
drugs containing perfluorinated compounds
food and beverages made with water that contains fluoride
waterproof and stain-resistant items with PFCs
Excess fluoride exposure may come from:
public water fluoridation
high concentrations of fluoride in natural fresh water
fluoridated mouthrinse or toothpaste
untested bottled water
inappropriate use of fluoride supplements
Not all fluoride exposure is due to adding the chemical to water and dental products.
Some geographical areas have drinking water that is naturally high in fluoride, for example, southern Asia, the eastern Mediterranean, and Africa.
Possible side effects of excessive fluoride intake include: