Fluoridated Water, ADHD Diagnosis and Healthy Eating: Economic Evidence

COMMENTARY

A new study published in the Journal of Health Economics provides compelling evidence that fluoridated community water harms Americans: Childhood exposure to it reduces high school graduation rates, physical ability and health, and economic sufficiency in adulthood.

Currently, the Centers for Disease Control and Prevention recommends water fluoridation, and many states and local governments mandate it.   

This study is the doctoral dissertation of Dr. Adam Roberts from Texas A&M University, who is now a financial economist at the Office of the Comptroller of the Currency within the U.S. Department of the Treasury. Among many data sources, Roberts obtained natural fluoride levels for most U.S. communities through a Freedom of Information Act request to the CDC. 

Using a sample of more than 20 million individuals, he compared those exposed to fluoridated water during childhood with those of the same age in the same county who were not exposed. He found that, despite its dental benefits, childhood fluoride exposure led to a net negative effect in adulthood, including lower high school graduation rates, reduced economic sufficiency, and poorer physical ability and health. These results are consistent with the findings of a meta-analysis published by JAMA Pediatrics in early January, which showed that fluoride exposure and children’s IQ are negatively associated.

This study exemplifies how economists use rigorous analytical tools and comprehensive data to answer complex medical and health questions.

Another example comes from Dr. Todd Elder, an economics professor at Michigan State University, who found that children whose birthdays are in the month prior to their state’s cutoff date for kindergarten eligibility (i.e., the youngest in the class) were substantially more likely to be diagnosed with attention-deficit/hyperactivity disorder than those whose birthdays fall in the subsequent month (i.e., the oldest in the class).  

Elder concluded that ADHD is often misdiagnosed due to teachers’ subjective comparative assessments of children within the same grade. The negative consequences are substantial, including adverse health impacts and financial burdens from ADHD treatments and medications.

Another study published in The Quarterly Journal of Economics, used supermarket entry and household moving data to find that personal demand explains 90% of the difference in the consumption of healthy vs. unhealthy food, with the remaining 10% explained by supply factors of healthy groceries. 

As the study’s author, Stanford University Professor Rebecca Diamond, and her five coauthors concluded, “Our results do allow us to conclude that policies aimed at eliminating food deserts likely generate little progress toward a goal of reducing nutritional inequality.” 

It is no coincidence that economists have been providing compelling evidence on medical and health issues. As the late economist Edward Lazear wrote in his renowned article, “Economic Imperialism”:

“Economics is not only a social science; it is a genuine science. Like the physical sciences, economics uses a methodology that produces refutable implications and tests these implications using solid statistical techniques. … The goal of economic theory is to unify thought and to provide a language that can be used to understand a variety of social phenomena. … The fact that there have been so many successful efforts in so many different directions attests to the power of economics.”

President Donald Trump signed an executive order on Feb. 13 to establish the President’s Make America Healthy Again Commission, which prioritizes “gold-standard research” and “transparency and open-source data.” 

If evidence-based decision making is truly enshrined in broad health-related policies and practices, we may look forward to more economic research helping to make America healthier.

Ge Bai is a professor of accounting and health policy at Johns Hopkins University. An expert on health care accounting, finance and policy, she has testified before Congress, written for The Wall Street Journal and The Washington Post, and published her studies in leading academic journals such as The New England Journal of Medicine, JAMA and Health Affairs. She can be reached on X.