LOS ANGELES – People who move from a poor neighborhood to a better-off one could end up thinner and healthier than those who stay behind, according to an urban housing experiment that tracked low-income residents in five major cities for 10 to 15 years.

The research, set up by the U.S. Department of Housing and Urban Development, shows that health is closely linked to the environments people live in — and that social policies to change those environments or move people away from blighted areas could be a key tactic in fighting the “diabesity” epidemic.

The study released Wednesday by the New England Journal of Medicine took advantage of a 1990s social experiment approved by Congress primarily to track the changes in income, education and employment of people given the opportunity to move out of low-income housing in Los Angeles, Baltimore, Chicago, New York and Boston. At least 40 percent of the residents at the start of the study made less money than the federal poverty threshold.

Researchers soon realized that the project could allow them to study residents’ changes in health as well, said study co-author Dr. Robert Whitaker, a pediatrician at Temple University in Philadelphia.

From 1994 to 1998, the researchers randomly divided 4,498 women who made less than the federal poverty level, and had children, into three groups. One-third were given a voucher that would pay for a portion of their rent, as long as they moved to a much-better-off area in which no more than 10 percent of residents had incomes below the poverty level. They were provided with counseling to help them make the move.

Another one-third were offered traditional vouchers, which would subsidize housing regardless of location. The final one-third served as the control group and did not receive vouchers.

Ten to 15 years later, researchers measured the women’s height, weight and blood sugar. They found that rates of extreme obesity among women given moving vouchers were about 19 percent lower than those who stayed in the low-income neighborhoods, and rates of diabetes were about 22 percent lower.

“This is one of the first studies to show that … your health is not just what happens to you,” said Dr. Harlan Krumholz, a cardiologist at the Yale School of Medicine, “but is influenced by all of those around you and the environment. … Some environments are toxic to health.”