“Organizations that have a long-term view of workers and investment in human capital would benefit from taking into consideration some of these findings,” Conroy said.

A deep dive into the body of research

The research examines much more than the rather obvious connection that highly paid workers have a larger budget to devote to medical expenses. The article casts a wide net in its analysis of past research, examining how pay impacts everything from workers’ physical condition such as disease and mortality, to ties to psychological symptoms as broad as depression, burnout and anxiety. The researchers also considered behavioral habits tied to health such as eating, sleeping and exercise habits, substance abuse and absenteeism.

Conroy and her coauthor’s investigation of the many facets of pay was equally expansive. They integrated previous research into pay levels, both absolute and relative to the market, as well as inequality of pay among workers in an organization. They also considered the impacts of pay-for-performance plans like piecework and commission structures.

“To my knowledge, our research is the first to really examine the breadth of the literature of all the different pay strategies, to understand health outcomes,” Conroy said.

It was no small task to wrap their arms around such a deep body of research. As the pair read previously published material, analyzing each piece’s focus, and how it positively or negatively impacted workers, they indexed each article in a database. After results were objectively analyzed and codified, researchers looked at the general trends unearthed by their comprehensive overview.

The results were clear. In nearly all cases, when workers received higher pay and fewer uncertainties about receiving it, their health and wellbeing improved. The lone exception? Conroy found that workers earning higher salaries suffered more cardiac events than their lower-paid counterparts.

The stress-pay-health connection

Rather than throwing the pair’s findings into uncertainty, the correlation between higher salaries and increased risk of heart problems is actually in line with their theory. The pair use the theory of allostatic load, the burden of day-to-day stress and its physiological and psychological impacts, as the throughline that connects generations of research into pay, health and wellbeing.

Generations of prior research point to the conclusion: People who earn more money simply have more resources to maintain their health and wellbeing, which eliminates the stresses linked to poor outcomes. While some of those are obvious – having the capacity to afford healthcare and medications, for example – the benefits of a more affluent lifestyle on health are staggering. Those not juggling multiple jobs have more time to exercise while more easily absorbing the costs associated with an active lifestyle. More paid time off and funds to travel provide the opportunity to relax and de-stress. Similarly, lower-paid workers more often struggle with psychological stresses, from worries about household budgets and managing tight finances. Negative feelings surrounding perceived inequities in pay, the anxiety of maintaining sufficient pay under fluctuating schedules or variable pay structures also contribute to this allostatic load.

The end result, the researchers found, was stress, and the inability to mitigate it, are more common among lower-paid workers of all types.

“When people are stressed, they release stress hormones and have a heightened heart rate to address the threat,” Conroy said. “The problem is if you’re overstressed chronically, then it gets under your skin and makes you sick. Negative health outcomes like heart disease are potential outcomes of that. Even mortality is as an outcome of that.”