Vitamin / mineral supplementation → Employment status
The archetypal smoke. Control for education, parental SES, and baseline income and the supplement→career effect goes to zero.
Observational · High confidence
The association does not survive the backdoor. Usually SES, outdoor time, or healthy-user bias.
Mechanism
Shrank, Patrick, and Brookhart (2011) describe the bias: adherers to preventive regimens have better outcomes even when the pill is a placebo. Multivitamin and omega-3 users are selected on conscientiousness, cash, and health anxiety. Those traits keep people employed.
Caveats
Correcting documented B12, iron, or D deficiency in deficient populations can restore function. That is a medical effect on a mediator (fatigue, cognition), not a career steroid.
Effect
qualitative. Healthy User Bias: the kind of person who buys vitamins is the kind of person who keeps a job.
Nodes
Named confounders
Cite this page
What Causes What. “Vitamin / mineral supplementation → Employment status.” https://whatcauseswhat.org/edges/e-supplements-employment (atlas updated 2026-08-31).
Papers
- Healthy user and related biases in observational studies of preventive interventions: a primer for physicians
W. H. Shrank, A. R. Patrick, M. A. Brookhart · 2011 · Journal of General Internal Medicine