Effect of early life exposure to a clean water intervention on health and socioeconomic status in adulthood: Evidence from a quasi-experimental cohort study in Mexico

Background: Early childhood diarrheal disease jeopardizes child development by diverting nutrition away from physical and mental growth towards fighting illness. Consequently, early exposure to clean water interventions, which reduce diarrheal risk, may confer positive effects on downstream adult health and well being, though such long-run benefits are typically not accounted for in resource allocation decisions. We examined the effects of early exposure to a nationwide clean water intervention in Mexico in 1991 on adult health and socioeconomic status. Methods: We used a quasi-experimental cohort design. Data on height, body-mass index (BMI), and schooling for over 20,000 individuals born between 1987-1993 were taken from a nationally representative 2012 survey. Diarrheal mortality data were taken from vital statistics. We compared outcomes for cohorts exposed to the clean water program in infancy versus those exposed afterwards, across states that benefitted most from the intervention.