Fluoride

Green and colleagues followed 512 Canadian mother-child pairs and found that each 1mg per litre increase in maternal urinary fluoride was associated with a 4.49 point lower IQ in boys. Published in JAMA Pediatrics in 2019, this replicated earlier findings by Bashash and colleagues in Mexico City, where higher prenatal fluoride exposure predicted 3.66 fewer IQ points per 1mg daily increase.

The National Toxicology Program completed a systematic review in 2024 covering 72 studies and concluded with moderate confidence that fluoride exposure at or above 1.5mg per litre is consistently associated with lower IQ in children. Eighteen of nineteen high-quality studies found this inverse association. The accompanying meta-analysis of 74 studies was published in JAMA Pediatrics in January 2025.

Birmingham became the first city in Britain to fluoridate its water supply in 1964. Today, roughly 6 million people receive fluoridated water, approximately ten percent of the population in England, concentrated in the West Midlands and parts of North East England. No new fluoridation schemes have been introduced since the 1980s.

The Health and Care Act 2022 transferred authority to introduce new fluoridation schemes from local councils to the Secretary of State for Health and Social Care, removing the requirement for local democratic consent. The government announced plans to expand fluoridation in parts of the North East, subject to public consultation, marking the first potential expansion in over four decades.

Peckham et al. (2015) in the Journal of Epidemiology and Community Health analysed hypothyroidism prevalence across England by comparing GP practices in fluoridated West Midlands with non-fluoridated areas. Practices in fluoridated areas were 30 per cent more likely to report high hypothyroidism prevalence (odds ratio 1.30, 95% CI 1.16 to 1.46). The association persisted after adjusting for age and sex demographics. The dataset covered every GP practice in England, approximately 7,935 practices serving 55.4 million patients.

This is because fluoride is a known inhibitor of thyroid peroxidase, the enzyme required for iodination of thyroglobulin and synthesis of T3 and T4 hormones. Fluoride at concentrations of 2 to 5 mg/day was prescribed as an antithyroid medication in the 1950s and 1960s to treat hyperthyroidism (Galletti and Joyet 1958). Modern fluoridated water at 0.7 to 1.0 ppm delivers approximately 1.4 to 2.0 mg/day for an adult drinking 2 litres, approaching the lower therapeutic dose used historically to suppress thyroid function.

The thyroid controls basal metabolic rate, body temperature, weight regulation, energy levels, mood and cognitive function. Subclinical hypothyroidism affects an estimated 4 to 10 per cent of the general population. If a 30 per cent increase in hypothyroidism is attributable to fluoridation, this represents hundreds of thousands of people in England alone living with a treatable endocrine disruption caused by a public health intervention that was never tested for thyroid safety.

Choi et al. (2012, Environmental Health Perspectives, Harvard School of Public Health) conducted a systematic review and meta-analysis of 27 epidemiological studies from China, Iran, India and Mexico. Children exposed to higher fluoride concentrations showed IQ scores averaging 7 points lower than children in low-fluoride areas. Twenty six of 27 studies demonstrated an inverse association between fluoride exposure and cognitive function. The effect remained significant after controlling for confounders including lead exposure, socioeconomic status and iodine deficiency.

This is because fluoride crosses the blood-brain barrier and accumulates preferentially in the hippocampus, the brain region most critical for learning and memory formation. Fluoride disrupts the synthesis of neurotransmitters (acetylcholine, glutamate, GABA) and increases oxidative stress in neural tissue. Mullenix et al. (1995, Neurotoxicology and Teratology) demonstrated fluoride accumulation in brain tissue of rats at blood concentrations comparable to those found in humans living in fluoridated water areas (1 ppm).

The National Toxicology Program (2020) subsequently confirmed the association in their own systematic review, grading the evidence as "moderate" for a link between fluoride and lower IQ in children. Despite this, the UK, USA and Australia continue to fluoridate public water supplies at 0.7-1.0 ppm, affecting approximately 370 million people worldwide. The original endorsement of water fluoridation in 1945 preceded the establishment of modern toxicological review standards by decades.

The WHO (Fawell et al. 2006) documented endemic skeletal fluorosis in 26 nations, with India, China and the East African Rift Valley most severely affected. India alone has an estimated 6 million cases. Skeletal fluorosis develops in three clinical stages: Stage I (preclinical) presents as joint stiffness and chronic musculoskeletal pain, easily misattributed to arthritis or ageing. Stage II involves calcification of ligaments and osteosclerosis. Stage III is crippling deformity with neurological complications from spinal cord compression.

This is because fluoride substitutes for hydroxyl groups in hydroxyapatite, the mineral matrix of bone, converting it to fluorapatite. At low chronic doses, this increases bone density on scans (often misread as "healthy" bone) while actually increasing brittleness and reducing tensile strength. Fluoride also stimulates osteoblast activity while impairing osteoclast function, leading to abnormal bone remodelling: more bone is deposited but it is structurally inferior. Ligament and tendon calcification occurs because fluoride stimulates mineralisation wherever collagen is present.

The relevance to fluoridated populations is that Stage I fluorosis (joint pain, muscle stiffness, chronic fatigue) is clinically indistinguishable from common complaints attributed to ageing, overwork or fibromyalgia. No routine clinical test exists to diagnose early skeletal fluorosis. The WHO threshold for skeletal fluorosis risk (4 mg/L in water) was set before modern total fluoride exposure (water, food, beverages, toothpaste, dental treatments, medication, tea) was quantified. Cumulative lifetime exposure in fluoridated communities may approach levels seen in mild endemic areas.

The NHS Centre for Reviews and Dissemination at the University of York published the most comprehensive systematic review of water fluoridation in the BMJ in 2000. After evaluating 214 studies, the review found zero randomised controlled trials. Evidence for effectiveness was graded low to moderate quality and the evidence on reducing dental health inequalities was described as "poor quality, contradictory and unreliable."

The review director, Professor Trevor Sheldon, publicly stated the findings had been "widely misrepresented" by the British Dental Association, British Medical Association and British Fluoridation Society. He clarified in a formal statement: "The review did not show water fluoridation to be safe. The quality of the research was too poor to establish with confidence whether or not there are potentially important adverse effects."

Approximately 10 per cent of the UK population (6 million people) receive artificially fluoridated water, primarily in the West Midlands and North East England. The Health and Care Act 2022 transferred fluoridation decision-making from local authorities to the Secretary of State for Health. In 2022, the government announced plans to extend fluoridation to the entire North East, which would be the first expansion in 25 years.

This is because fluoride is classified as a Group 1 chemical (systemic effects with narrow margin of safety) by the European Commission, and the European Court of Justice ruled that fluoridated water meets the definition of a medicinal product under EU pharmaceutical law. Most European countries have rejected fluoridation: 97 per cent of Western Europe does not fluoridate. Germany, France, Belgium, Netherlands, Sweden, Denmark, Norway, Finland, Austria, Switzerland, Italy, Spain and Portugal have all either banned it, discontinued it, or never implemented it.

The dose-response debate is central: a 70 kg adult drinking 2 litres of fluoridated water at 1 mg/L receives 2 mg of fluoride daily. A 10 kg toddler drinking 1 litre receives 1 mg, producing a per-kilogram dose 3.5 times higher. No other medication is administered through the water supply with no control over dose, no informed consent, no monitoring of individual blood levels and no ability to opt out without installing filtration equipment.

Ninety-seven percent of Western Europe does not fluoridate its water supply. Austria, Belgium, Denmark, Finland, France, Germany, Iceland, Italy, Luxembourg, the Netherlands, Norway, Sweden and Switzerland have all rejected or discontinued the practice. Only Ireland mandates fluoridation in Europe, covering roughly 73% of its population.

The reasoning is consistent across borders. Germany calls it "compulsory medication." France cites "ethical as well as medical considerations." The Netherlands stopped fluoridation in 1976 after a Supreme Court ruling that water "should not be used as a vehicle for pharmaceuticals." Belgium states it is "not the task of the drinking water sector to deliver medicinal treatment to people."

Luke (2001) conducted the first study measuring fluoride accumulation in the human pineal gland. Analysing 11 cadavers from a fluoridated community, she found mean fluoride concentrations of 296 mg/kg (dry weight) in pineal gland calcified tissue, higher than any other soft tissue in the body and comparable to bone (highest recorded: 875 mg/kg). The study also found elevated fluoride in the uncalcified pineal tissue itself, averaging 37 mg/kg.

This is because the pineal gland sits outside the blood-brain barrier and has a very high blood perfusion rate (second only to the kidney). Its tendency to form hydroxyapatite calcifications (corpora arenacea) creates a perfect trap for fluoride ions, which substitute for hydroxyl groups in the crystal lattice. Once incorporated, fluoride is not mobilised or excreted. It accumulates across the lifespan. The pineal gland is the primary producer of melatonin, the hormone regulating circadian rhythm, sleep architecture, antioxidant defence and reproductive timing.

The implication is that a gland weighing less than 0.2 grams, responsible for regulating the most fundamental biological rhythm in the human body, is being chronically loaded with a calcifying agent from municipal water supplies. Luke's follow-up animal studies found that fluoride-exposed gerbils had earlier puberty onset and reduced melatonin production. No government fluoridation programme has ever measured or monitored fluoride accumulation in the pineal gland as a safety endpoint.

The Institute of Medicine estimates that chronic fluoride intake of 10mg or more per day for 10 or more years can produce skeletal fluorosis, a condition characterised by joint stiffness, ligament calcification and bone hardening. In its early stages, skeletal fluorosis closely mimics arthritis and is frequently misdiagnosed. The WHO set its drinking water guideline at 1.5mg per litre specifically to prevent skeletal accumulation.

Adults in fluoridated communities consume an estimated 1.6 to 6.6mg of fluoride daily from water, food, tea and toothpaste combined. Black tea alone contains approximately 2.6mg per litre. The margin between average daily intake and the damage threshold is narrower than commonly recognised, particularly for heavy tea drinkers or those regularly swallowing fluoridated toothpaste.

In 1939, biochemist Gerald Cox at the Mellon Institute, founded by the family behind ALCOA (then America's largest aluminium producer and a major generator of fluoride waste), became the first researcher to propose adding fluoride to public water supplies. Grand Rapids, Michigan began fluoridation in January 1945 with nearby Muskegon as the unfluoridated control city in a planned 15-year comparative study.

The American Dental Association endorsed fluoridation in 1950, just five years in. Muskegon added fluoride to its own supply in 1951, eliminating the control group after only six years. Edward Bernays, nephew of Sigmund Freud and the father of public relations, was hired to sell the programme to the American public, later telling journalist Christopher Bryson that doing so was "child's play."

Reverse osmosis systems remove 90 to 99% of fluoride from drinking water. Distillation achieves over 99% removal. Activated alumina filters remove 70 to 90%, though performance depends heavily on water pH. These methods work but require dedicated installation, regular maintenance and cost several hundred pounds.

Standard carbon jug filters, the type most British households actually own, remove approximately five percent of fluoride. They are not certified for fluoride reduction and were never designed for it. The majority of people in fluoridated areas who believe their filter is protecting them are removing virtually nothing.