The objective of this study was to evaluate the association between several acculturation surrogates and obesity, a well-known risk factor for CVD. Among Peruvian rural-to-urban migrants, we demonstrated that obesity was associated with age at first migration, language proficiency, and language preferences.
Reasons for migration depend upon life phase (16
). Those migrating before adolescence travel with their families who migrate to improve their economic status, having better opportunities for education, but they are also more likely to become more acculturated, which has a greater impact on their behavior and consequently on their health (17
). In our report, however, the odds of obesity, using both markers separately, was greater at older age at migration. These contradictory findings could be explained by environmental exposures, including nutrition patterns. Diet among population from Andean regions is based on carbohydrates, which might influence migrant’s health; however, this hypothesis requires confirmation. Previous reports described the effect of acculturation on obesity among migrants, who mostly migrated to developed countries for economic reasons (6
). Mass-migration in Peru, however, largely took place for the purpose of escaping from terrorism rather than for economic reasons (20
). In that sense, this population was not simply a small self-selected group. It is therefore essential to use other study designs for appropriate analysis of the impact of migration on health among this type of population.
Language has been also used as acculturation surrogate in previous reports, including fluency and preferences in social interactions (10
). In our context, Quechua is the usual language in Andean rural areas, while Spanish is the common language in urban areas. Many studies have previously reported the association between language and over-weight related behaviors (5
), and health practices (21
). In our study, we show an association between obesity and self-reported ability to speak Spanish. Thus, greater acculturation, measured as self-reported fluency in Spanish, was a risk factor for obesity after adjusting for potential confounders. This observation follows the same direction as that observed in Latino populations living in the US where better language (English) fluency is a sign of greater acculturation (8
Preference for listening Spanish, however, was associated with lower odds of obesity. Although our model was adjusted for potential confounders, we found opposite results compared to language proficiency. This study therefore expands on the available literature suggesting that measures of language proficiency and preference, although related, do not assess acculturation in the same way. As recently reported, language preference (for listening in this case) tends to reflect participants’ underlying cultural values, but also social networks, political ideology, and social identity (23
). Thus, the interpretation of questions regarding language preference might change depending on the participants’ context and background. On the other hand, language proficiency may directly influence access to health care and broader social determinants of disease (23
). Language preference might be an indicator of migrants’ adoption of unhealthy lifestyles, a marker of acceptance of health-promoting practices, or a proxy for language proficiency and barriers to health access (24
). In this study, we believe that language preference for listening in Spanish amongst within-country migrants – assessed by ideal language for listening to radio programs – could either be a marker of enhanced attitudes or access towards health promoting practices. However, complex studies are needed to improve our understanding of the mechanisms and interactions between variables. Longer residence in urban environment was not associated with obesity as having been reported in previous studies (6
Strengths of this study include the use of a well-defined within-country migrant population, the assessment of several surrogates of acculturation on obesity, as well as the use of two different obesity indicators. Both obesity indicators have been independently associated with CVD and mortality. While BMI relates to overall obesity, WC assesses mainly abdominal obesity and mainly the amount of visceral fat (25
). However, cut-offs derived from other populations for use in our population have been questioned. In this manuscript, using proposed WC cut-offs for our population, we could reach similar results using BMI. This study, however, has some limitations. First, the sample size was small compared to previous studies, which prevents a complete evaluation of the association between acculturation and obesity. Second, although age at first migration and language preference were associated with obesity, dietary patterns were not measured. This could explain the inverse association found in this study compared to other studies (9
). Finally, acculturation is a complex process, comprising multiple dimensions, and cannot be completely evaluated through simple variables or cross sectional studies. Although we used previously reported variables associated with chronic diseases and health-related conditions; further studies are needed to confirm our findings.
In conclusion, acculturation is a process affecting rural-to-urban migrants. Length of residence, age at migration, language proficiency, and language preferences are easily evaluable surrogates that can be used to assess the migration and health association among within-country migrants. While traditionally acculturation surrogates have been described to be associated with negative health outcomes, largely interpreted by the adoption of negative lifestyle risk factors, in this paper we report some findings in the opposite direction. That is, acculturation considering language preference for listening in Spanish - the hosting language - showed lower odds of obesity. This reflects that acculturation per se can also explore positive channels associated with better health outcomes. Different approaches and more complex studies with greater sample sizes are needed to more fully understand mechanisms of unhealthy behaviors in low- and middle-income countries.