| Abstract: |
Between the early 1980s and 2002, both the prevalence of obesity and the
number of beneficiaries of the Social Security Disability Insurance program
doubled. We test whether these trends are related; specifically, we test
whether obesity causes disability and movement onto the disability rolls. We
estimate models of instrumental variables using two nationally representative
data sets, the Panel Survey of Income Dynamics and the National Longitudinal
Survey of Youth, 1979 Cohort. The results are mixed but we find evidence that
weight increases the probability of health-related work limitations and the
probability of receiving disability related income. Our results suggest that
the failure to treat obesity as endogenous leads to dramatic underestimates of
the link between obesity and disability outcomes. Authors’ Acknowledgements We
thank seminar participants at Ohio State University and the 2004 Conference of
the Social Security Retirement Research Consortium for their helpful comments.
We gratefully acknowledge financial support from the University of Michigan
Retirement Research Consortium and the Bronfenbrenner Life Course Center at
Cornell University. We thank Shuaizhang Feng for expert research assistance. |