Is your hometown making you overweight?

The number of obese Americans is expected to increase to 113 million by the year 2022, making the U.S. the most overweight country in the world.

Despite huge investments to treat obesity, progress has been slow. That isn’t stopping two College of Nursing researchers from trying.

Shannon Zenk, associate professor of nursing, and Elizabeth Tarlov, assistant professor, received a four-year, $2.3 million federal grant to investigate how residential environment factors may be linked to weight.

The grant is from the National Cancer Institute, one of the National Institutes of Health.

More than one-third of adults are obese, and less than half of those who attempt to lose weight succeed in shedding a clinically significant amount, Zenk said. Of those who do lose weight, few keep it off.

Shannon Zenk, associate professor of nursing.

“These disappointing outcomes challenge researchers and policymakers to consider how the residential environment can be used to increase healthier eating habits and physical activity,” she said.

Previous research attempted to link environmental factors and body weight, but whether the residential environment affects long-term weight trajectories remains an open question, Tarlov said.

Elizabeth Tarlov, assistant professor of nursing.

The new study will examine data from more than 1 million American veterans to determine whether local features — such as areas to walk, aesthetics, nearby recreational sites and availability and cost of healthy and unhealthy food — affect body weight and metabolic risk such as blood pressure, serum glucose and lipids.

The study will look at data from more than 200,000 veterans who have participated in a weight management program and a similar number of controls, said Tarlov, a research health scientist at Hines Veterans Administration Hospital.

This second phase of the study will examine whether the residential environment affects individuals’ ability to lose weight at six months, maintain weight loss at 18 months and achieve healthier weight over five years.

The new research will provide “the most robust evidence to date that is needed to formulate effective public health policies to eradicate obesity,” Zenk said.

“It has the potential to fundamentally transform weight management intervention approaches.”

The project is funded by the National Cancer Institute.