Ocean air may add years to your life, research shows

Researchers from The Ohio State University analyzed population data -- including life expectancy -- in more than 66,000 census tracts throughout the U.S. and compared it based on proximity to waterways. Their study was published online in the journal Environmental Research.

A correlation between longer life expectancy and water was clear for those who live within about 30 miles of an ocean or gulf. But for those who live in urban settings and near an inland body of water larger than 4 square miles, the opposite was true. Rural residents who live near water may also reap some lifespan advantages, according to the research.

"Overall, the coastal residents were expected to live a year or more longer than the 79-year average, and those who lived in more urban areas near inland rivers and lakes were likely to die by about 78 or so. The coastal residents probably live longer due to a variety of intertwined factors," said lead researcher Jianyong "Jamie" Wu.

The analysis suggested that milder temperatures, better air quality, more opportunities for recreation, better transportation, less susceptibility to drought, and higher incomes could all be contributors to a better outlook for coastal residents compared to those who live inland.

"On the other side, pollution, poverty, lack of safe opportunities to be physically active and an increased risk of flooding are likely drivers of these differences," said Yanni Cao, a postdoctoral researcher who worked on the study.

The most critical difference the researchers found is that coastal areas experience fewer hot days and lower maximum temperatures compared to inland water areas.

Previous research has found a connection between living near water and better health measures, including higher physical activity levels, lower obesity rates and improved heart health. That prompted Wu to wonder if there could be a link between "blue space" living and longer lives, and how that relationship might differ depending on the type of neighborhood people call home, he said.

"We thought it was possible that any type of 'blue space' would offer some beneficial effects, and we were surprised to find such a significant and clear difference between those who live near coastal waters and those who live near inland waters," said Wu, an assistant professor of environmental health sciences at The Ohio State University College of Public Health.

"We found a clear difference -- in coastal areas, people are living longer," said Wu, adding that the study is the first to comprehensively and systematically examine the relationship between various types of "blue space" and longevity in the U.S.

Cao said she was especially curious about how this data might provide insights into the trends in life expectancy in the U.S. compared to other wealthy nations. In the past several years, the U.S. experienced a sharper decline and a slower rebound in life expectancy than peer countries.

"It's likely that various social determinants of health, including complex environmental factors, that contribute to health inequities are playing a key role in the differences we saw," she said.

Ria Martins, a graduate student in public health, was also a co-author.