In image: a child rinses a toothbrush in San Francisco on June 18, 2019. THE CANADIAN PRESS/AP-San Francisco Chronicle, Gabrielle Lurie Gabrielle Lurie
For decades, adding fluoride to drinking water has been a key strategy in improving dental health across North America. Experts credit the practice with reducing tooth decay, especially among people with limited access to dental care. However, the debate over water fluoridation has recently gained momentum in some communities, with critics citing potential health risks linked to fluoride exposure.
Fluoridation began in the 1940s in parts of Canada and the U.S. as a measure to prevent cavities. Today, practices vary widely by region. For example, while most Ontarians have fluoridated water, many communities in British Columbia, Newfoundland, and Quebec do not.
In the U.S., opposition has been amplified by figures like health secretary nominee Robert F. Kennedy Jr., who has pledged to end water fluoridation nationwide. In Canada, discussions have also resurfaced about the benefits and risks of this decades-old public health measure.
Benefits of Fluoridation
Health authorities, including Health Canada and the Canadian Dental Association, argue that fluoride strengthens tooth enamel and prevents cavities, the most common chronic disease among children worldwide. Fluoridated water is particularly beneficial for those who may not brush regularly or see a dentist often.
Studies highlight the benefits. Research from the University of Calgary compared children’s dental health in Calgary, which stopped fluoridation in 2011, with Edmonton, where it continued. Over seven years, Calgary children had significantly more cavities. In 2021, Calgary voters supported reintroducing fluoride to their water, which is expected to resume in 2025.
Concerns Over Risks
Despite its benefits, some studies raise concerns about fluoride exposure. A 2023 Health Canada review found no conclusive evidence linking current fluoridation levels (0.7 mg/L) to neurocognitive issues. However, other research, including a 2019 York University study, found a possible association between higher fluoride exposure during pregnancy and lower IQ scores in children.
The U.S. National Toxicology Program also identified a link between high fluoride levels (twice the recommended limit) and reduced IQ in children, though it emphasized insufficient data to determine risks at lower levels. Some critics argue more research is needed before continuing widespread fluoridation.
Regional Variations
Fluoridation decisions are typically made at the municipal level in Canada. As of 2022, only 38.8% of Canadians receive fluoridated drinking water, with significant regional disparities. For instance, while 73% of Ontarians have fluoridated water, less than 2% of residents in British Columbia and Quebec do. Cost and health concerns are often cited as reasons for opting out.
Economic Considerations
While implementing fluoridation can be expensive initially, proponents highlight its long-term savings in dental care costs. Health Canada estimates a high return on investment, with communities saving up to $93 for every dollar spent on fluoridation.
For example, Calgary stopped fluoridation in 2011 to save $750,000 annually. However, reinstating it will cost an estimated $28 million—a price some argue will ultimately save the city money in reduced dental treatments.
Is Fluoridation Still Necessary?
Some researchers suggest fluoride’s benefits may be less critical today, especially in areas where toothpaste and dental care are widely available. A 2023 review by the Cochrane Library found that fluoridation’s impact has declined since the 1970s when fluoride toothpaste became common. However, the review noted fluoridation might still help in underserved communities.
Experts remain divided. While critics point to evolving science and potential risks, others argue fluoridation is a simple, cost-effective measure to improve public health.
“Why not do it when some people will benefit, others may not, but nobody is harmed?” said Joe Schwarcz, director of McGill University’s Office for Science and Society. For now, the decision to fluoridate water continues to rest in the hands of individual communities, shaped by both science and public opinion.
