Consistent evidence reveals greater odds of obesity among U.S.-born Mexican-Americans relative to their first generation counterparts. This study extended this comparison by including those in Mexico, and revealed the gap between first generation immigrants and the U.S.-born is one part of a graded increase in obesity associated with migration to the U.S.. This is important in light of a longitudinal analysis that suggested first generation immigrants may be resistant to the obesogenic environment in the U.S. (ref) This cross-sectional comparison suggests otherwise. We found slight differences by gender, but results indicate a roughly three fold increase in obesity from one extreme to the other for both sexes.
Secondly, we found that among Mexicans with no direct migration experience, having a migrant in the immediate family is associated with higher risk for obesity among women, but not for men. This finding may reflect economic influences on diet such as cash remittances sent by migrants working in the U.S.
Findings should be interpreted in light of the use of cross-sectional data and reliance on self-report of height and weight. Self-reports tend to underestimate the prevalence of obesity, but evidence suggests that self-report does not differ between immigrant and U.S.-born Mexican-Americans, except for those who are underweight. 9
Migration is a transnational process that is likely to have a range of health effects in both sending and receiving countries, including diet. Given that obesity is a risk factor for the major causes of mortality in this country, growing rates among Mexican-Americans is of public health and clinical urgency.