Early-Life Nutrition and Subsequent International Migration: A Prospective Study in Rural Guatemala

BACKGROUND: It is generally accepted that migrants are favorably self-selected for labor market skills such as higher schooling and greater cognitive capacity, which are highly correlated with early-life nutrition. However, the influence of early-life nutrition on later-life migration is understudied. OBJECTIVE: The objective of this study was to examine prospectively the association between height-for-age z scores (HAZ) at 24 mo and subsequent international migration in a cohort of 2392 participants born between 1962 and 1977 in 4 rural villages in eastern Guatemala. METHODS: Information on nutritional status and covariates was collected between 1969 and 1977 and migration status was determined as of 2017 (at ages 40–57 y). We used proportional hazards and logistic regression models to assess whether HAZ was associated with international migration, adjusting for early-life and adult characteristics. RESULTS: Between 1978 and 2017 there were 297 international migrants (12.4% of the original cohort) during 99,212 person-y of follow-up. In pooled models that were adjusted for early-life characteristics, a 1-SD increase in HAZ was associated with a 19% increase in the risk of international migration (HR: 1.19; 95% CI: 1.02, 1.38). Further adjustment for village characteristics did not alter the estimate substantively (HR: 1.18; 95% CI: 1.02, 1.37), while additional adjustment for schooling attainment attenuated the estimate somewhat (HR: 1.14; 95% CI: 0.98, 1.33). In all models, effect sizes were stronger for men than for women. CONCLUSIONS: Our results indicate that early-life nutrition is positively associated with subsequent international migration.