From the Guidelines
Excessive fluoride exposure can have several negative health impacts, including dental fluorosis, skeletal fluorosis, neurological effects, and gastrointestinal issues, though moderate amounts in drinking water and dental products are generally considered safe. High fluoride intake can cause dental fluorosis, which appears as white spots or streaks on teeth, and in severe cases, skeletal fluorosis, which involves bone pain, stiffness, and increased bone fracture risk [ 1 ]. Neurological effects may include reduced IQ in children exposed to very high levels during development, as shown by a meta-analysis that found greater exposure to high levels of fluoride in water was significantly associated with reduced levels of intelligence in children [ 1 ]. Thyroid function can be impaired as fluoride may interfere with iodine uptake. Gastrointestinal issues like nausea, vomiting, and abdominal pain can occur with acute high-dose exposure. These concerns primarily arise with excessive exposure well above recommended levels (typically over 4 mg/L in water).
Key Points to Consider
- Most public water fluoridation programs maintain levels around 0.7 mg/L, which balances dental benefits against potential risks [ 1 ].
- If concerned about fluoride intake, you can use fluoride-free dental products, drink filtered water, and be mindful of fluoride content in tea and certain foods, though completely eliminating fluoride is unnecessary and could reduce protection against tooth decay.
- The need for fluoridation remains debated, and some authors consider that artificial water fluoridation should be reconsidered globally [ 1 ].
- Fluoride can reasonably be provided in enteral nutrition (EN) at doses of up to about 3 mg/day, and in parenteral nutrition (PN) at a dose of 0.95 mg without any side effects, and with the potential for beneficial effects on bones and teeth [ 1 ].
Recommendations for Safe Fluoride Intake
- Adults typically consume <0.5 mg of fluoride daily in food, and nutritional intakes in adults are safe up to 4 mg/day in men and 3 mg/day in women [ 1 ].
- Fluoride might also have an impact on children's neurological development, and studies are ongoing to investigate this further [ 1 ].
- Poisoning most commonly follows ingestion of fluoride-containing products, and treatment includes minimizing absorption by administering a solution containing calcium, monitoring and managing plasma calcium and potassium concentrations, acid-base status, and supporting vital functions [ 1 ].
From the Research
Negative Impact of Fluoride on Health
- There is evidence to suggest that high concentrations of fluoride can be toxic and have negative impacts on health 2, 3, 4.
- Acute toxicity can occur after ingesting one or more doses of fluoride over a short time period, which can lead to poisoning 2.
- The risk of fluorosis is associated with the ingestion of high doses of fluoride during tooth development, and consequently, only young children are at risk 3, 4.
- Toothpastes with higher fluoride concentration increase the risk of fluorosis (enamel defects) in developing teeth 4.
- The variability in the dose of fluoride ingested is mainly a function of the amount used, less so its concentration, and to minimize fluorosis risk, parents should be advised to use only a pea-sized amount of toothpaste and encourage spitting out of excess 3.
Safe Use of Fluoride
- The topical use of fluoride is safe, and the European Academy of Paediatric Dentistry (EAPD) recommends a preventive topical use of fluoride supplements because of their cariostatic effect 2.
- Fluoride toothpastes are clinically proven to prevent and control dental caries, and well-formulated fluoride toothpastes can maximize the benefit and minimize the risk 3, 5.
- The choice of fluoride toothpaste concentration for young children should be balanced against the risk of fluorosis 4.
- Supervised toothbrushing with fluoridated toothpastes can have a superior preventive effect compared to unsupervised brushing 5.