Explained: What is fluoride and why is it in drinking water? | US elections 2024

What is Fluoride?

Fluoride is a mineral common in nature that is released from rocks into soil and water. Certain plants – including plants consumed by humans such as tea – absorb and concentrate fluoride.

“It is not an industrial waste product. It is a natural substance,” said Prof Oliver Jones, Professor of Chemistry at RMIT University.

Fluoride has been added to drinking water and toothpaste for decades because it strengthens teeth and prevents tooth decay.

When fluoride is incorporated into tooth enamel, it forms a mineral called fluorapatite, which is more resistant to acids, said Prof Loc Do, professor of public dental health at the University of Queensland. “It makes tooth enamel more resistant to bacteria that cause tooth decay,” he said.

The World Health Organization's safe limit for fluoride in drinking water is 1.5 milligrams of fluoride per liter of water – or 1.5 parts per million. The typical concentration of fluoride in regular toothpaste is between 1000 and 1500 parts per million.

Since when has fluoride been added to drinking water?

In the early 20th century, dentists noticed that tooth decay rates were lower where people had mottled discoloration on their teeth – a condition caused by excess fluoride and now known as dental fluorosis. They found that areas with naturally higher levels of fluoride in the water had lower tooth decay rates.

In 1945, Grand Rapids, Michigan became the first place in the world to add fluoride to its drinking water. Fluoridation is not mandatory and voluntary in the United States, but in 2012, more than 67% of the total U.S. population had access to fluoridated tap water.

In 2011, the U.S. Department of Health and Human Services lowered the recommended level of fluoride in drinking water to 0.7 milligrams of fluoride per liter – 0.7 parts per million. Five decades earlier the upper limit was 1.2.

Does fluoride in water have health effects? Is it safe?

A number of international health authorities have classified fluoride in drinking water as effective and safe. The U.S. Centers for Disease Control and Prevention named fluoridation one of the ten greatest public health interventions of the 20th century.

Contrary to Kennedy's claims, studies have found no evidence that fluoride in regular drinking water is linked to conditions such as osteoporosis, bone fractures or cancer.

As with any chemical compound, ingesting fluoride in high amounts can cause harmful effects such as: B. Dental fluorosis – a condition indicated by discoloration of the teeth – and skeletal fluorosis, a condition in which fluoride is incorporated into the bones. These only occur with chronic fluoride exposure that is well above the limits for safe drinking.

“At high enough concentrations, everything is poison — even water,” Jones said.

In August, the US National Toxicology Program released a report suggesting a link between fluoride exposure above 1.5 milligrams of fluoride per liter of water and lower intelligence quotients in children. However, experts point out that there is a lack of high-quality research on the topic.

“Some studies … have been identified as being at high risk of bias in other systematic reviews,” Do said. Do's own research has found no association between drinking fluoridated water before age 5 and changes in behavioral development or executive function.

In which countries is fluoride added to water?

Dozens of countries around the world are artificially fluoridating their drinking water. In 2012, approximately 435 million people worldwide had access to water containing fluoride at recommended levels.

The United States, United Kingdom, Canada, New Zealand, Australia and Brazil are all among the countries adding fluoride to water in at least some regions.

Do said adding fluoride to water is a good way to reduce socioeconomic inequality in dental health. “It’s a passive way to reduce dental caries.”

What could change if Donald Trump wins the US election?

Kennedy, whom Donald Trump has promised to put in charge of health initiatives, said Saturday that if elected president, the Republican would push to remove fluoride from drinking water on his first day in office.

Kennedy has emerged as one of Trump's top surrogates after leaving office as an independent candidate. On Sunday, Trump told NBC News that he and Kennedy had not discussed fluoride but that the plan “sounds OK to me.”

Why was fluoride removed from water in the past and what were the effects?

Authorities in several jurisdictions have removed fluoride from drinking water by public order, for example in Calgary, Canada in 2011, or by ministerial decree, for example in Israel in 2014.

Research shows that in Calgary, after the end of fluoridation, the number of dental caries in children increased, while in Israel the number of dental procedures increased significantly. Calgary is expected to reintroduce fluoridation in 2025.

Germany stopped fluoridating its water in the 1970s and never reintroduced it, but has sold salt with added fluoride since 1991.