A recent initiative of the United States Centers for Medicare & Medicaid Services (CMS) to allow states to add a work requirement to Medicaid eligibility has been justified in part on evidence that work is beneficial for health. But the relationship between work and health is much more complex than first appears.

There is no question that our work lives and our health are intimately related. We spend much of our lives at work. The things we do at work and our workplace environment have a major impact on our habits and behaviors and on the things we are exposed to every single day. Unacknowledged as it is in much health research, work is perhaps the single most important determinant of the health of adults, but the impact is not always positive.

An obvious example is workplace related injuries. According to the United States department of Labor, 5,190 workers were killed on the job in 2016, more than 14 deaths every day. [https://www.bls.gov/news.release/cfoi.nr0.htm].  Worldwide it is estimated that more than 350,000 workers a year die from work-place related injuries. The numbers of workplace related non-fatal injuries are of course orders of magnitude higher.

Many other adverse exposures occur at work. A classic example is the radiation poisoning developed by women workers (the "Radium Girls") who painted watch dials with radium-laden paint in New Jersey, Connecticut, and Illinois in the early 1900s. Apparently, supervisors encouraged workers to point the brushes with their lips ("lip, dip, paint"). Many more recent examples abound: think of asbestos exposure among construction workers, auto mechanics, shipbuilders and many others; or pesticide exposure among workers in the flower industry (yes, the source of those beautiful flowers that often decorate our homes).

Workplaces have also contributed to epidemics of chronic disease.  Sedentary jobs are a major cause of physical inactivity. Computer-intense jobs are linked to multiple musculoskeletal disorders. Easy access to junk food, along with short lunch breaks, can also promote unhealthy eating habits. Many psychosocial aspects of work, such as lack of control over the work process and other work stressors  (including excessive demands at work and a perceived imbalance between effort at work and rewards), are associated with high blood pressure and other cardiovascular disease outcomes.

Of course, work can have many benefits for health as well. To the extent that work translates into improved living conditions such as better housing, more educational opportunities, and increased material resources it can promote health. And of course it can be a source of social connection and support—so important to health. It can also be fulfilling and creative, which if not directly linked to health, certainly improves quality of life. But these benefits occur over long periods and in jobs that are secure, that minimize adverse exposures and sources of stress and that are well-compensated and rewarding. Unfortunately, recent surveys suggest that in the US, these conditions are not met for many workers.

Many studies have shown that the unemployed are less healthy than the employed, but one cannot conclude from this that employment always causes better health.  Although unemployment can sometimes adversely affect health, many unemployed persons are unemployed because of their health. Good health is a prerequisite for keeping a job and being successful at work. And poor quality low paying jobs have been linked to poorer, not better, health. In fact, a recent study found that unemployed adults who transitioned into poor quality jobs actually experienced adverse health consequences as evidenced by a range of biomarkers.

What is clear from the evidence we have is that the healthfulness of work depends on the type of work and the context in which that work occurs. It would be naïve to assume that any type of work is health promoting. Many of us who are fortunate to have jobs that allow for creativity, that give us flexibility, and that reward us materially and in many other ways, have never experienced the ways in which work can also be numbing and draining, and a source of mental and physical stress and despair.

Promoting health is not about promoting or requiring any work at any cost. It is about promoting work that is fulfilling and rewarding materially and in other ways. It is about increasing variety, support, and control at work. It is about work in health promoting environments. It is about not sacrificing other healthful things, such as personal or family time, or (in the case of Medicaid recipients) benefits such as health insurance (the loss of which can itself adversely impact health,) for any type of job.

The link between work and health is perhaps the best example of the profound and fundamental way in which our social organization and the way our economy functions determine population health. How can work be designed, organized, distributed and shared across society so that it really promotes health and health equity? Acting to improve health in ways that address these fundamental determinants, while avoiding simplistic explanations remains our greatest challenge.

Ana V. Diez Roux, MD, PhD, MPH
Dean and Distinguished Professor, Epidemiology, Dornsife School of Public Health