TUESDAY, Dec. 14, 2004 (HealthDayNews) -- The longer immigrants live in the United States, the more likely they are to take on what has become an increasingly common American characteristic: obesity.
A new study has found that immigrants who have lived in this country for at least 15 years are nearly as obese as their U.S.-born counterparts. The weight gain seemed to start after people had been living in the United States for 10 years.
"It's amazing how quickly people are changing," said Dr. Mita Sanghavi Goel, lead author of a report on the trend that appears in the Dec. 15 issue of the Journal of the American Medical Association.
"Within 15 years, they are more likely to look like someone who is U.S.-born than a recent immigrant," said Goel, an instructor in medicine at Northwestern University's Feinberg School of Medicine in Chicago "It's another alarm bell."
Immigrants currently comprise more than 11 percent of the U.S. population, larger than many minority groups. In all, more than 127 million American adults are overweight, and almost 70 million are obese or severely obese.
One previous study had found that staying longer in the United States was associated with obesity. This study, however, tried to pin down when the weight gain happened and how much it was.
Goel and her colleagues analyzed data provided by 32,374 people for the 2000 National Health Interview Survey. Fourteen percent of the respondents were immigrants. The prevalence of obesity was 16 percent among immigrants, and 22 percent among U.S.-born individuals.
Only 8 percent of immigrants who had lived in the United States for less than one year were obese, vs. 19 percent of those who had been living in the United States for at least 15 years. This association was seen for all immigrant subgroups except foreign-born blacks.
For a typical 5-foot-4-inch immigrant woman, there was a nine-pound weight gain, and for a typical 5-foot-9-inch immigrant man, the increase was 11 pounds.
This weight gain was over and above any gain due to other factors such as age, income level, and race or ethnicity.
Although the study was not designed to understand precisely why this was happening, Goel had a theory. "Imagine you're a recent immigrant coming to the U.S.," she said. "You might live in an urban center where there are other immigrants similar to you, shop at local grocery store, prepare traditional foods. You may not have a car and so you walk around more."
Then imagine that your job changes or you have children and move outside of that original neighborhood. Now you might start picking up more American habits, buying candy at the checkout lane, and driving more than walking.
"Immigrants become Americanized rather quickly," added Maritza Marchante-Henry, a nutritionist with New York City's Visiting Nurse Service who originally hails from Cuba. "They want to be Americanized. They are confronted with a large variety of different foods, including a lot of the fast food sources which are very high in fat and high in sodium and some are also high in sugar."
To complicate matters, the study found that immigrants were less likely than U.S.-born individuals to report discussing diet and exercise with health-care providers (18 percent vs. 24 percent).
This failing may also provide an opportunity, especially with recent immigrants. "Immigrants generally tend to be healthier when they first come to the U.S.," Goel said. "That changes over time. This is the ideal population to talk with about maintaining healthy behaviors."
But health-care providers are only a small part of the puzzle, Goel added. Additional changes also have to take place in society.
"The larger policy implications are our access to healthy foods and how we as a society can figure out how to carry foods that are actually healthy. Are they too expensive for people to buy? Or is it harder to find fruits and vegetables?" she said. "Is it too easy to get in a car and drive someplace? Maybe we need to create an environment that fosters walking around."
Visit the U.S. Centers for Disease Control and Prevention for more on overweight and obesity.