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Fluoride

Somewhat controversial - there's no doubt fluoridation helps with 'dental caries' but disagreement about the downsides.

Potential downsides;

  • dental mottling, referred to as dental fluorosis
  • bone cancer (osteosarcoma)
  • Down’s syndrome
  • effects on the kidney
  • long term exposure to high levels of fluoride can lead to dental Fluorosis in children and skeletal Fluorosis
  • there are concerns and some research that it may also cause a rare type of bone cancer (Osteosarcoma) and impair brain development in children
  • osteoporotic fracture 5

Toothpaste

Fluoridation of Water

Fluoridation of the general water supply is intended to prevent tooth decay, specifically caries - which most of us call cavities. Most research on fluoridation is from the 70s (before it was added to toothpaste). Unlike most research we come across, it's mostly statistics (as you'll see further down) rather than cause and effect, pathways, mechanism of action and the like - this makes me very 'suss' - where are the controlled trails, double blinds, replication studies and so on???

Rarely done in Europe. Around 70% of water in the US: https://www.cdc.gov/fluoridation/about/?CDC_AAref_Val=https://www.cdc.gov/fluoridation/basics/index.htm

Fluoride is not commonly added to the water supply in the UK apart from a few regions in England; Birmingham, Crewe, Lincoln, Newcastle upon Tyne, Scunthorpe & Workington1 which represents around 10% of the population (6-7 million people at the time of writing). Naturally occurring concentrations which meet the target levels of fluoridation schemes (which is one milligram per litre (mg/l), or 1ppm) or something close to it are present in the water supply in parts of Bath, Cambridge, Newbury & Norwich. For information on other parts of the world see: the Wikipedia article on Water fluoridation by country. Only these companies fluoridate water, in some areas, in the UK (as of 2025-01-18);3

  • United Utilities
  • Northumbrian Water
  • Anglian Water
  • Severn Trent Water
  • South Staffordshire Water

Fluoride is also found in low levels in almost all vegetables. Tea has particularly high levels.

As there is with calcium, is there also a need for Vitamin D to aid absorption?

The UK government's latest (2022) Water fluoridation: health monitoring report for England, which focusses on the dental health of children and young people and is produced every four years, provides the following short 'lay summary';

  • Five-year-olds in areas with higher fluoride concentrations were less likely to experience dental caries, and less likely to experience severe dental caries, than in areas with low fluoride concentrations.
  • Five-year-olds in areas with a fluoridation scheme in place were less likely to experience dental caries than in areas without a scheme.
  • Children and young people in areas with higher fluoride concentrations were less likely to be admitted to hospital to have teeth removed (due to decay) than in areas with low fluoride concentrations.
  • Children and young people in areas with a fluoridation scheme in place were less likely to be admitted to hospital to have teeth removed (due to decay) than in areas without a scheme.
  • These effects were seen at all levels of deprivation, but children and young people in the most deprived areas benefited the most.

You'll note the focus on children and young people - that's because evidence of a benefit in adults is limited. This article references some NHS research that suggests the benefits in adults are marginal: https://www.manchester.ac.uk/about/news/future-benefits-of-water-fluoridation-not-guaranteed-study-shows/. The study referenced is 4

Naturally occurring, with some areas having very high natural levels in water.

Dosage

The World Health Organization (WHO) recommends a maximum level of 1.5 milligrams of fluoride per litre of water (mg/l)2.

The UK follows the WHO recommendations with a maximum permitted value of fluoride in drinking water of 1.5mg/l (milligrams per litre) and a recommended value of 1.0mg/l.3.

Maximum

Side Effects

Random Facts

References

  1. Delivering better oral health: an evidence-based toolkit for prevention - Published 12 June 2014 ↩

  2. Guidelines for drinking-water quality: fourth edition incorporating the first and second addenda - Published 21 March 2022 ↩

  3. Fluoridation of Drinking Water - 2025-01-18 ↩↩

  4. Moore D, Allen T, Birch S, Tickle M, Walsh T, Pretty IA. How effective and cost-effective is water fluoridation for adults? Protocol for a 10-year retrospective cohort study. BDJ Open. 2021 Jan 21;7(1):3. doi: 10.1038/s41405-021-00062-9. PMID: 33479223; PMCID: PMC7820470. ↩

  5. Hillier S, Inskip H, Coggon D, Cooper C. Water fluoridation and osteoporotic fracture. Community Dent Health. 1996 Sep;13 Suppl 2:63-8. PMID: 8897754. ↩