Scientists Can Predict Your City’s Obesity Rate by Analyzing Its Sewage

The sewage of fat cities like Little Rock and Toledo is easy to distinguish from that of skinny ones like Denver and San Diego.<a href="http://www.shutterstock.com/pic-126763280/stock-photo-young-fat-woman-and-young-woman-lean.html?src=csl_recent_image-2">Shutterstock</a> <a href="<a href="http://www.shutterstock.com/pic-146217686/stock-vector-dotted-usa-map-on-blue.html?src=csl_recent_image-1">photo</a></a> <a href="http://www.shutterstock.com/pic-222996850/stock-vector-a-cartoon-illustration-of-a-piece-of-poop-waving-and-smiling.html?src=csl_recent_image-3">collage</a>

Fight disinformation: Sign up for the free Mother Jones Daily newsletter and follow the news that matters.


If someone were to ask you what distinguishes skinny cities from fat ones, you might think of the prevalence of fast-food joints, the average length of automobile commutes, or the relative abundance of parks and jogging trails. But there’s also another, more underground factor: their sewage.

Researchers with the University of Wisconsin-Milwaukee collected raw sewage samples from the intakes of municipal wastewater treatment plants in 71 cities around the country. Their results, published last month in mBio, the American Society for Microbiology’s open-access journal, showed that the microbial content of that sewage predicted each city’s relative obesity with 81 to 89 percent accuracy.

The finding actually isn’t all that surprising, says lead author Ryan Newton, a visiting professor at UWM’s School of Freshwater Sciences. Other studies have shown that bacterial imbalances in your intestines can lead to metabolic syndrome, obesity, and diabetes. Newton’s study, however, is the first to demonstrate that those microbial differences also play out across entire populations, even after our poop gets flushed, mixed together, and sent through miles of pipes.

The UWM study was enabled by computing advances that have allowed scientists to rapidly sequence microbial populations and look for patterns in the results. Other researchers are using similar techniques to look for correlations between gut bacteria and a wide range of health conditions.

Scientists hope other data derived from sewage could help predict epidemics and track public health trends.

Newton isn’t the only scientist who sees sewage as a promising place for data dives. The Massachusetts Institute of Technology’s Underworlds project, which began in January, will study sewage for the presence of viruses such as influenza and polio; bacterial pathogens that cause cholera typhoid fever, and other diseases; and biochemical molecules ranging from antibiotics to illegal drugs like cocaine and methamphetamine. Scientists hope the resulting data could help predict epidemics and track other public health trends within particular neighborhoods. 

As scientists gain a better understanding of the interplay between microbes and human health, they may eventually be able to look at municipal sewage to figure out which communities would be the best to target with public health campaigns designed to, say, get people to eat less sugar or more vegetables.

And just as important, sequencing sewage could eliminate the thorny problem of doing public health surveys. Unlike people, your poop can’t lie about what you had to eat.

LET’S TALK ABOUT OPTIMISM FOR A CHANGE

Democracy and journalism are in crisis mode—and have been for a while. So how about doing something different?

Mother Jones did. We just merged with the Center for Investigative Reporting, bringing the radio show Reveal, the documentary film team CIR Studios, and Mother Jones together as one bigger, bolder investigative journalism nonprofit.

And this is the first time we’re asking you to support the new organization we’re building. In “Less Dreading, More Doing,” we lay it all out for you: why we merged, how we’re stronger together, why we’re optimistic about the work ahead, and why we need to raise the First $500,000 in online donations by June 22.

It won’t be easy. There are many exciting new things to share with you, but spoiler: Wiggle room in our budget is not among them. We can’t afford missing these goals. We need this to be a big one. Falling flat would be utterly devastating right now.

A First $500,000 donation of $500, $50, or $5 would mean the world to us—a signal that you believe in the power of independent investigative reporting like we do. And whether you can pitch in or not, we have a free Strengthen Journalism sticker for you so you can help us spread the word and make the most of this huge moment.

payment methods

LET’S TALK ABOUT OPTIMISM FOR A CHANGE

Democracy and journalism are in crisis mode—and have been for a while. So how about doing something different?

Mother Jones did. We just merged with the Center for Investigative Reporting, bringing the radio show Reveal, the documentary film team CIR Studios, and Mother Jones together as one bigger, bolder investigative journalism nonprofit.

And this is the first time we’re asking you to support the new organization we’re building. In “Less Dreading, More Doing,” we lay it all out for you: why we merged, how we’re stronger together, why we’re optimistic about the work ahead, and why we need to raise the First $500,000 in online donations by June 22.

It won’t be easy. There are many exciting new things to share with you, but spoiler: Wiggle room in our budget is not among them. We can’t afford missing these goals. We need this to be a big one. Falling flat would be utterly devastating right now.

A First $500,000 donation of $500, $50, or $5 would mean the world to us—a signal that you believe in the power of independent investigative reporting like we do. And whether you can pitch in or not, we have a free Strengthen Journalism sticker for you so you can help us spread the word and make the most of this huge moment.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate