Mexican-American youth add pounds as they lose native eating habits

According to the research, conducted by a team in the Arnold School of Public Health and published in the February issue of the Journal of Nutrition, Mexican-American youth born into second- and third-generation families are more likely to be obese than those who were not born in the United States.

"Mexican-American children are disproportionately affected by obesity," said Dr. Jihong Liu, the lead author of the paper. "This has serious public health consequences because Mexican Americans are the fastest growing segment of the population. They are a very important population to study."

Few studies have examined the impact of both immigration and a child's acculturation on obesity, she said. "Most are focused on adults, who are at increased risk for obesity with each generation."

Second-generation Mexican Americans were 2.5 times as likely to be obese as their first-generation peers; third-generation Mexican Americans were two times more likely to be obese.

Researchers looked at data from nearly 2,300 Mexican-American youth between the ages of 12 and 19 who participated in the 1999 -- 2004 National Health and Nutrition Examination Survey (NHANES). The survey measures height and weight of participants, as well as factors that gauge acculturation, including nativity for parents and the child and a child's language preference, such as reading, thinking and speaking in a particular language at home, with family members or friends.

The study found that 63 percent of the participants spoke some English; 21.5 percent spoke only English, and 16 percent spoke little English. Nearly 73 percent of the youth were second- or third- generation Mexican American.

According to the study, adolescents from second and third generations have diets high in saturated fat and sodium, and they consume high levels of sweetened beverages. Their consumption of fruits, vegetables, grains, meat and beans was lower than first-generation Mexican-American youth.

A typical Mexican diet includes corn, beans, meat such as pork and fish, fruits, including pineapple and papaya and vegetables such as squash and avocado.

"Our findings suggest that Mexican-American adolescents face challenges in terms of poorer diet and excessive weight gain associated with their immigration and acculturation experience," said Liu, a researcher in the Arnold School's department of epidemiology and biostatistics. "This verified what we expected: the greater the acculturation that a young person has experienced, the less healthy their diet."

The implication of the study is that young people who are more likely to be acculturated need help and support to maintain a healthy diet, she said.

Although the study did not address the causes, Liu said many immigrant families have a lower socioeconomic status and therefore cannot afford to buy fruits and vegetables and healthier foods, which are more expensive.

"Our findings also suggest that policies and programs should be in place to help immigrants protect their traditional dietary practices such as a high consumption of fruit, vegetables, and bread while they assimilate to the American culture and society," Liu said. "Future studies should continue to examine the barriers that Mexican-American adolescents encounter in maintaining their native diet and identify strategies to address those barriers."

Arnold School researchers Dr. Edward Frongillo, Dr. Janice Probst, and Mr. Yong Chu, a doctoral candidate, contributed to the study, which was supported by the Maternal and Child Health Research Program of the U.S. Health Resources and Services Administration.