The United States Government Accountability Office (GAO) has issued a report on the effect of work hours on health.  GAO found that very long work hours may modestly increase certain adverse health outcomes.  To read the GAO report on the effect of work hours on health, use the first link below.  To read GAO highlights of the report on the effect of work hours on health, use the second link below.

https://www.gao.gov/assets/gao-24-106772.pdf  (GAO report on the effect of work hours on health)
https://www.gao.gov/assets/gao-24-106772-highlights.pdf  (GAO highlights on the effect of work hours on health)