A study of the height of Mexican children whose mothers worked in maquiladoras (export factories) in Mexico dramatically illustrates the power of a good job. Maquiladoras generally have the reputation of being exploitative and paying poor wages. However, for many women without a high school education, the establishment of the maquiladoras offers the prospect of a better job than the jobs in retail, food services, or transportation that would otherwise be their lot--the hourly wages are not much higher, but they work longer hours and with more regularity. David Atkin, from Yale University, compared the height of children born to mothers who lived in a town where a maquiladora opened when the woman was sixteen years old to that of children of mothers who did not have this opportunity. The children whose mother's town had a maquiladora were much taller than those born to similar women in different towns. This effect is so large that it can bridge the entire gap in height between a poor Mexican child and the "norm" for a well-fed American child.
Furthermore, Atkin shows that the effect of a job in a maquilladora on the level of family income is nowhere near large enough to explain the entire increase in height. Perhaps the sense of control over the future that people get from knowing there will be an income coming in every month--and not just the income itself--is what allows these women to focus on building their own careers and those of their children. Perhaps this idea that there is a future is what makes the difference between the poor and the middle class.
Abhijit Banerjee and Esther Duflo, Poor Economics, p228.
The study referenced is: David Atkin, "Working for the Future: Female Factory Work and Child Height in Mexico," working paper (2009).