Calculating the costs of a nationwide fluoride ban

Fluoride has been added to public drinking water in the United States since 1945 to strengthen tooth enamel and fight off bacteria, ultimately reducing tooth decay. However, several U.S. states have recently announced bans on the addition of fluoride to their public water systems, and there has been speculation that a nationwide ban may not be far behind.  A new study published in JAMA Health Forum, reveals the impact a ban would have on dental health, showing a substantial increase in dental decay and costs, particularly for publicly insured and uninsured children.

Researchers from Mass General Brigham and Harvard School of Dental Medicine used a simulation model to estimate dental health outcomes for children if the U.S. were to ban fluoridation of public water. The study focused on children because fluoride is known to strengthen teeth at a critical time in tooth development. 

“Fluoride replaces weaker ions within tooth enamel, making it stronger and less susceptible to tooth decay caused by bacteria,” said senior author Lisa Simon MD, DMD, a dentist and physician in the Division of General Internal Medicine at Brigham and Women’s Hospital. “There’s strong evidence from other countries and cities showing that when fluoride is eliminated, dental disease increases. Our study offers a window into what would happen in the United States if water fluoridation ceased.”

The study used detailed oral health and water fluoridation data collected from 8,484 children (ages 0–19, 49% girls) in the nationally representative National Health and Nutrition Examination Survey (NHANES). Using this dataset, the researchers developed a microsimulation model to see how banning fluoride from drinking water would impact oral health, quality of life, and dental care costs over 5- and 10-year periods, which align with policy planning horizons. First, maintaining current fluoride levels, and second, eliminating the addition of fluoride to public water. 

"Using a simulation model to track the progression of diseases in current populations, we estimated the impact of removing fluoride on the risk of tooth decay and the related dental care costs, including treatment for decay and complications from delayed treatment. We ran the simulation 1,000 times to see how different factors could affect the results. This approach helps ensure that our predictions are more reliable and reflective of real-world variability,” said first author Sung Eun Choi, PhD, assistant professor of Oral Health Policy & Epidemiology at Harvard School of Dental Medicine.

Simon and Choi found that eliminating fluoride increased the total number of decayed teeth by 7.5 percentage points, or 25.4 million more teeth with tooth decay over five years (equivalent to a tooth for one out of every three American children). The number of fluorosis cases—a discoloring of tooth enamel due to excessive fluoride intake—decreased by 0.2 million. They also estimated $9.8 billion in additional dental care costs over five years, which rose to $19.4 billion after 10 years.