Drinking filtered water is linked to an extended lifespan, according to recent research published in the American Journal of Health Economics. The study highlights that exposure to water filtration systems early in life can significantly boost longevity. By examining shifts in public health infrastructure from the early 20th century, researchers determined that city water filtration added an average of 3.2 months to the lifespan of older American men.

Jason Fletcher, a professor at the University of Wisconsin–Madison, emphasized the study’s findings in a press release, stating, “While water quality has improved in many areas, this study shows the real impacts on communities without access to safe water, both in the U.S. and globally. The consequences on human health are significant.”

The research team utilized data from the Social Security Administration’s Death Master Files. They tracked the death records of American men born between 1975 and 2005, linking each individual’s year and city of birth to historical water filtration records. This approach allowed them to connect early-life environments with late-life outcomes, demonstrating the long-term impact of clean water.

Beyond adding months to an individual’s life, the study suggests that access to clean water during childhood sets off a positive ripple effect on socioeconomic and physical development. Mid-20th-century census data revealed that early exposure to filtered water correlated with increased height, higher education, and greater income levels later in life.

This paper forms part of a broader research initiative known as the American Mortality Project, which explores how conditions in early life influence the modern American lifespan. However, the study primarily analyzed historical data from American men, meaning it may not fully reflect the effects on women or individuals from rural areas or other countries.

The data analysis focused on public health infrastructure changes across U.S. cities during a specific period in the late 19th and early 20th centuries, indicating that the timeline and magnitude of the lifespan extension might not directly apply to present-day developing nations or different environments.