By Karin Zeitvogel

WASHINGTON, May 17, 2011 (AFP) – Immigrants to the United States often ditch their ethnic diets for high-calorie American fare, partly because it is cheap and easy to find but also as a way to fit in, a new study shows.

Immigrants who eat American are consuming, on average, 182 extra calories and seven additional grams of saturated fat compared to immigrants who stick to their traditional diet, leaving the fast-food immigrants more likely to become obese and suffer chronic illnesses related to obesity.

In fact, immigrant children who have lived in the United States for 15 years are as prone to obesity as American-born kids, one in three of whom is overweight or obese, says the study by researchers from the University of Washington, University of California-Berkeley and Stanford University.

Earlier studies have identified the phenomenon of “dietary decline after arrival in the US” in many immigrant groups, including from Africa and Latin America.

But the researchers in this study, conducted by the US-born child of Indian immigrants, Sapna Cheryan; the daughter of Chilean immigrants, Maya Guendelman; and French immigrant Benoit Monin, focused on whether Asian-Americans “consume American foods… to convey that they belong in America.”

In the first of two experiments conducted for the study, a group of Asian-Americans was “threatened” by being asked if they could speak English, and then asked to note down their favorite food. A control group noted down their preferred dish without having their American-ness “threatened.”

“‘Do you speak English’ doesn’t seem so bad on the face of it, but if you’re the target, it does feel that you’re being singled out because of the way you look or your skin color,” Cheryan told AFP.

The threatened group in the first experiment was three times more likely than the unthreatened group to say they liked a typical American dish like macaroni and cheese or a hamburger best.

In the second experiment, Asian-Americans were asked to choose from items on a menu listing typically American fare like bacon, lettuce and tomato sandwiches, fried chicken, hot dogs and hamburgers; or one featuring Asian fare like sushi, pad Thai rice noodle dishes, or chicken teriyaki.

Sixty percent of participants whose American identity was questioned — they were told they “had to be an American” to be in the experiment — chose food from the US menu while the majority of those in the non-threatened control group – 70 percent — chose items from the Asian menu.

The Asian-Americans who were trying to assert their U.S. identity after having it challenged were eating “the caloric and fat equivalent of an extra four-piece order of McDonald’s Chicken McNuggets over those who were not threatened,” says the study.

That adds up over time, and even though immigrants have a lower rate of obesity when they arrive in the United States, switching to American food is helping them to catch up to US-born Americans, one in four of whom is obese, says the study, which will appear in the June issue of Psychological Science.